Robert Cialdini (3:31)

Here's an example. One of my colleagues here in the Cialdini Institute that I work with, Eilee, is a Brit by birth, but she and her family moved and she reports getting messages from her cousins about this energy drink called prime, which was scarce in the uk. In fact, there were long lines outside of the shops to get it because they significantly under supplied those shops and made it scarce.

Phil Agnew (4:04)

And this scarce availability allowed shop vendors to dramatically increase the price of prime drinks. Here's ITV News reporting on the story. Customers have reported traveling the country to smaller corner shops to get their hands on them. This guy said he spent £100 on a prime haul. £103.

Robert Cialdini (4:21)

92.

Phil Agnew (4:22)

Take you for a bill and you'll have seen this bloke on TikTok. His shop's been selling bottles for 20 quid. That is 10 times more than the big supermarkets have been selling them for, with this family apparently spending a grand on the drink. So it's no surprise that Cialdini's colleague Eileen was inundated with requests and she.

Robert Cialdini (4:41)

Could you send us a case of it? Because we can't get it here. The fact that they couldn't get it here made it more scarce and made it more valuable as a consequence.

Phil Agnew (4:52)

Prime energy drink is a fantastic scarcity example, because since that news story in 2022, nothing has changed about the energy drink. It's still the same drink. The only difference is it's now widely available. You can get it at almost every store for £2. And that means today it's not a scarce resource. And without that scarcity, prime drinks have lost their demand. UK revenue fell from 112 million in 2023 to to 32 million in 2024. Profits dropped by 78% over the same period. The scarcity was what made prime so attractive. Once it became abundant, demand dropped. But other companies leveraged scarcity in a more reliable and repeatable way than prime energy drinks did.

Robert Cialdini (5:40)

You can see that Disney does this with its classic movies like Pinocchio and Snow White and the Seven Dwarfs and Cinderella. They take them out of the vault every so often. You can now get them and then they put them back in the vault after a period of time, you can't get them anymore.

Phil Agnew (6:02)

Your last chance to own Disney's ultimate fairy tale, Sleeping Beauty, no Time to Lose, and the classic musical masterpieces Fantasia and Fantasia 2000.

Robert Cialdini (6:11)

Because on January 31, these hits are.

Phil Agnew (6:13)

Going back into the Disney vault. Get them before they're gone.

Robert Cialdini (6:16)

It makes people pile in to those things because they are scarce, rare and often dwindling in availability. That's a reason why for me, when I talk to groups about the scarcity Principle, I say, what do you have that's unique that your rivals can't provide? Right? And it may not be one thing, but it might be a suite of things that in combination, nobody else can provide. Put that at the top of your messaging because people will lean in to the rest of it because they know that they can't get this item or service anyplace else. That needs to go up front and get people processing your message because what you have to offer is unique. Uncommon. Yeah.

Phil Agnew (7:14)

In the book Happy Money, the authors give a fantastic example of this. It's KFC's Double Down Burger. The new KFC Double Down Burger. Double the chicken, double the fun for a limited time only grab it before it's gone. This burger is very unique. KFC debuted the Double down today. This is a bunless sandwich made of two pieces of fried chicken with bacon and cheese and secret sauce in between. Naturally, a bunless sandwich with two slabs of chicken acting as the bun is benefiting from scarcity because the food is just so unique. That's what Cialdini was saying. But KFC go further. They limit access to the burger. Usually it is only available to purchase for a couple of weeks each year. It was last available in the UK from 13 October to 9 November 2025. So this dual use of scarce access and uniqueness of the product made the burger incredibly successful. Well, it just might be the most outrageous sandwich experience you've ever sunk your teeth into. And now it is available in Canada. The Double Down, KFC's newest sandwich debuted in Canada today. By two this afternoon it had sold out at the Douglas street kfc. A disappointment to die hard fans.

Robert Cialdini (8:26)

I got a flyer in the mail like a couple weeks ago and it.

Phil Agnew (8:29)

Said it was going to be here on today, so I kind of cut.

Robert Cialdini (8:34)

It out and made A shirt.

Phil Agnew (8:35)

KFC calls the Double down an occasional indulgence, which is why it's only available in Canada for a limited time until November 14th. And it wasn't just Douglas street where KFC sold out of Double down burgers. Elizabeth Dunn in Happy Money writes that when the sandwich made its debut in 2010, KFC said 1 million double downs were sold in less than a month. In Canada, that is, and in America, 10 million were sold in a month. Its success keeps giving. They have been pulling this same trick, which is putting double down on the menu and then pulling it off the menu. Well, they've been doing this for 15 years and it still rakes in significantly high sales. It brings people to the fast food brand. Look, I really like this scarcity example. This mixture of a unique product with limited supply feels like a smart way to grow sales and excite customers. But this use of scarcity is rather different from the traditional use of scarcity that was really popularized by booking.com we've all seen booking.com's scarcity tactics. You go to book a hotel room and booking.com suddenly tell you that there are only two rooms like this available at the price. Cialdini writes that when Booking.com first included this online information about the limited number of hotel rooms that were still available, purchases skyrocketed. In fact, they skyrocketed to such a height that Booking.com's own customer service team called the technology office to report what they thought was a systems error because of the sheer number of bookings coming through. But I wondered if this type of scarcity had started to become outdated. I asked Cialdini if he thought that this was was still the right way to use the scarcity principle.

Robert Cialdini (10:10)

Here's what booking.com was slapped on the wrist for. They were right. There's only two rooms in the hotel like this available at this price. And they were right about that. Right? But the next price was like a dollar more. It wasn't a meaningful scarcity, right? And so they were not ethically advising us as to the representativeness of that scarcity. So they're not allowed to do that anymore. And as a result, because of that negative publicity, people are much more skeptical of what they say in this regard. And that's the lesson for all of us. If you are using these principles in a way that that misinforms or deceives your customer base, it will come back and bite you. You're going to lose authenticity, you're going to lose credibility as a consequence, and you will Have a more skeptical audience for anything you have to say, even if it's absolutely true and meets all of the requirements of representative scarcity, because people are now suspicious.

Phil Agnew (11:26)

In 1975, a researcher, Warchell and his colleagues had participants rate identical cookies but from different jars. One group was given a jar containing 10 cookies and the other group was given the same 10 cookie jar, but then had it quickly replaced with a two cookie jar. So a jar with just two cookies in it. Those who saw the 10 cookie jar and then the two cookie jar rated the cookies as considerably more tasty than those eating from the 10 cookie jar. And that's kind of expected. We rate scarce items higher, and when we see that a jar quickly gets swapped out for one that is smaller, the cookies suddenly became a scarce resource and we value them higher. However, a variant of Warchell's study proves Cialdini's point that matching your scarcity claim with a relevant bit of information makes the claim far more effective. See, the researchers in the cookie study created scarcity in two ways. Cialdini writes how certain participants were told that some of the cookies had to be given away to others in order to supply the demand for them. In the study, another set of participants simply told their allotment had to be reduced because the researcher had made a mistake and given them the wrong jar. Initially, some were told the jar was changed due to the item being in demand. Others were told it was just a mistake. The results show that those whose cookies became scarce through the process of social demand liked the cookies significantly more than those whose cookies became scarce by mistake. In fact, the cookies made less available through social demand were rated the most desirable of any cookie in the study. Don't create fake scarcity like booking.com. instead, link your scarcity to something real. So don't say limited to 3 per customer. Say it's limited due to 3 per customer due to high demand. Say we've restricted supply after unprecedented sales. Say no burritos today due to high popularity, fake scarcity won't work. People become suspicious. Believable scarcity is far more effective.

Robert Cialdini (13:19)

You know, I saw something that, that I love that shows how this suspiciousness works and a little honest technique to remove it. Let's say you have a toothpaste and you're honestly able to say that most people, most dentists do recommend this toothpaste. It's a good toothpaste. They'll say, yeah, I would recommend this toothpaste. And if you say 9 out of 10 dentists recommend us, you Get a bump. If you say 90% recommend us, you get an extra bump because you're being more precise. Right. And here's the one I love. The biggest bump comes from saying 89% of dentists recommend us. You're being honest. You showing that you're not just leveling this over the details and just saying 9 of 10 or whatever. No, no, you're giving people the exact percentage, even if it's less than 90%. They want it more now because it's coming from a credible source.

Phil Agnew (14:41)

I've spoken a lot on Nudge before about the specific numbers effect, about how sharing a specific number rather than a rounded one makes your claim more believable. In fact, NudgeVault subscribers have access to 27 different tips on how to apply this principle. So I won't harp on about it again. But I was happy to see that Cialdini uses this principle himself on his own website. Head to cialdiniinstitute.com and you'll see a five star rating at the top of the page. In fact, it says rated 4.6 stars out of 5 based on 23,949 reviews. Very precise.

Robert Cialdini (15:15)

We're not padding anything. We're not saying 40,000. We're not doing that. We won't do it. We're going to give people exactly the right, the right number. And so, for example, if you're ever in a situation where you're, you have a budget that you're recommending for a project that you want to do or a sale that you want to have, and you do all your calculations and you see that this is to cost 120 and 112 pounds to do this properly. And what you do is lop off the 112. You say it's a. We'll charge you £120,000 for this. Wrong. If you include the 112, you get less pushback on price because they recognize that you've done your homework. Even though it's more than the flat number, the round number, you get less pushback because you've established your credibility.

Phil Agnew (16:18)

Cialdini says this specificity, the precise number, actually allows the messenger to benefit from another principle.

Robert Cialdini (16:26)

This is the principle of authority that we also talk about in the seven Principles. An authority communicator is not just competent, that communicator is also trustworthy. If you have those two features, competence, credible, experienced, knowledgeable, and you combine that with truthfulness, nobody can beat you as a communicator. That's what we found around the world. Nobody can beat a credible authority who has demonstrated their credibility as knowledgeable and trustworthy.

Phil Agnew (17:10)

We'll cover the authority principle after this quick break. Content is Profit, hosted by Louise and Fonzie Camejo, is brought to you by the HubSpot Podcast Network, the audio destination for business professionals. Content is Profit is the podcast I'd love to recommend today because it shares the secrets and strategies behind what the hosts call a frictionless sale. Louise and Fonsi talk about frameworks, strategies, tactics and bring in special guests to bring you all the information you need to turn your content into profit. Back in December, they recorded with a YouTuber who reached 76,000 subscribers in just a year. To learn how go and listen to Content Is Profit. Wherever you get your podcasts, every idea starts with a spark, that moment of inspiration that fuels brilliant strategy. But what if you could find it instantly? Meet agentspark, your human insights assistant from gwi. It delivers fast data backed audience intel so you can get inspired, sharpen your thinking and build campaigns around real consumer behavior. And you'll receive fresh insights in seconds so you can validate hunches on your target audience and make smarter decisions. Backed by rock solid data ready to spark your next big idea? See it in action@gwi.com spark hello and welcome back. You are listening to Nudge with me Phil Agnew and the brilliant Robert Cialdini. So far, Cialdini's been taking us through the principle of scarcity. But to end today's show, he'll cover the authority principle.

Robert Cialdini (18:46)

I make a distinction and it's a very important one. It's the difference between being in authority and being an authority. Being in authority is about power. It's about the ability to move people by ordering them to do something. Otherwise you're going to penalize them or, you know, if they don't. That works, but it has social capital costs. People don't like being pushed and coerced into an action and they will come back and and push back against that when you're not around to to watch what they're doing, right? But if you are an authority, you have established yourself as a credible source of information that they can employ to decide what to do. Remember I said that when people are uncertain, they don't look inside themselves for answers. And one place they look is to peers. The second place they look is to the genuine authorities who are knowledgeable and experienced on a particular topic. They want to follow that person's advice under those circumstances because this person is giving them information they didn't have as non authorities.

Phil Agnew (20:16)

Authority is such a powerful principle of persuasion because it literally changes our perception. Cialdini writes how in Wilson's 1968 experiment conducted on five classes of Australian college students, a man was introduced as a visitor from Cambridge University in England. However, his authority at Cambridge was represented slightly differently to each of the classes. To one class he was presented as a student. From Cambridge to a second class he was presented as a demonstrator. To another he was presented as a lecturer. And yet to another a senior lecturer. And to the fifth class he was presented as a professor from Cambridge University, England. After he left the room, the class was asked to estimate his height. Is he 5 foot 10? Is he 6 foot 2? And they found something amazing. With each increase in authority, the man grew in perceived height by an average of a half inch, so that he was seen as 2 and a half inches taller when he was presented as a professor than as to the student.

Robert Cialdini (21:16)

So a good example is, I don't know if you have this particular TV commercial in the uk. We have it in the US for Toyota and they are promoting their Toyota certified repair centers. And they depict a guy who goes up to the desk and says, why would I want to pay the expense of a Toyota certified repair center?

Phil Agnew (21:44)

Okay, so why use Toyota service centers?

Robert Cialdini (21:47)

And the woman behind the desk says.

Phil Agnew (21:50)

Well, you wouldn't use just any carpenter, would you?

Robert Cialdini (21:53)

And then you see a flashback in this guy's mind where he remembers the last time he hired an uncertified carpenter who made a mess. And they do the same thing with plumber and they do the same thing with furniture mover and they remember how they wrecked, you know, Edwardian table that was in your family for all. And they, they established themselves as knowledgeable and competent and it's been very successful for them that that set of commercials.

Phil Agnew (22:27)

Applying the authority principle is surprisingly easy. Cialdini shares examples in his book. Having the CEO sign your letter makes the letter more likely to be actioned. Incredibly, paying an actor who has impersonated a doctor to promote your medicine will make your medicine seem more effective. Cialdini even shares a 2011 study by two researchers at Tilburg University. Cialdini writes that shoppers were more willing to comply with a request to participate in an unpaid survey if the requester was wearing a shirt or sweater that showed a prestige designer label. So if you're wearing Tommy Hilfiger, you're more likely to get someone to agree with your request. What's more, the differences were striking. 79% more compliance with the survey request when the requester wore the high quality T shirt. Just wearing some high quality clothes with a high quality brand is enough to trigger authority. We've covered a lot today how those in authority seem taller, why precise numbers are more believable, how to use scarcity in an effective way, and even the rise and fall of prime energy drink. But I wanted to end today's episode with a reader's report from Cialdini's book. In Cialdini's latest edition of Influence, he includes emails he received from readers who saw Cialdini's principles in the wild. This one is titled from a woman living in Poland. She writes, A few weeks ago I was a victim of one of the techniques you write about. I was quite shocked because I'm not the type of person who is easy to convince and I just read Influence, so I was really sensitive to those strategies. There was a little tasting booth in the local supermarket. A nice girl offered me a glass of beverage. I tasted it and it wasn't bad. I then she asked me if I liked it. After I answered yes, she proposed to me to buy four tins of this drink. She was using the principle of consistency. I liked it, therefore I should buy it and also the rule of reciprocity. She gave me something for free, but I wasn't so naive and I refused to do it. However, this saleswoman didn't give up. She said maybe only by wanting. So here she was using Cialdini's rejection then retreat tactic. But I didn't give up there either. Then she said this drink was imported from Brazil and she didn't know if it would be available at the supermarket in the future. The rule of scarcity worked and I bought the tin. When I drank this at home, the flavour was still okay. It was fine, but it was not great. Fortunately, most of the salespeople I speak to aren't so patient and persistent. I really can't stress how fantastic Robert Cialdini's books are. I'd go as far to say that his original book Influencer genuinely changed my life. They got me interested in the world of behavioural science and inspired me to learn more about the topic and to start this podcast almost seven years ago. Now I run the podcast full time and you could argue that without Cialdini's book I wouldn't be here today. So I highly recommend buying a copy. I've left a link to his book Influence and all his other books in the show notes. Cialdini's book not only triggered a chain of events that led to this show, but also to the Nudge Vaults, my brand new product. A database of 452 evidence backed insights from the world of behavioral science that are easy to understand and apply. If you want to take the two principles we've spoken about today, scarcity and authority, and you want to apply those principles to your work, then the Vaults is for you. For example, say you're writing an email and you want to apply scarcity and authority. Well if you simply add those filters into the database, you will find three specific insights from two peer reviewed papers with five tips on how you could improve your emails using both scarcity and authority. But as Cialdini taught me, you shouldn't just take my word from it, you should take it from someone in authority. So here is Miranda Renney, co founder and director at the award winning Weir Agency. I am Miranda Renney and I'm the co founder of Behavioural Change Water Savings Agency called We're the Agency. I gave Miranda early access to the vault back in March and here's what she said after using it for a few weeks. And I loved the vault, the nudge vault of every different piece of research or experiment that you, that you related to us in sort of high concept. You could go and read the paper and the access to that was invaluable. I want it all the time. If you think you might want vaults as well, then go to nudgepodcast.comvaults, that's nudgepodcast.comvaults or click the link in the show notes and if you do you can learn more about it on the website. But you can also Preview your first 50 insights for free. Alright, that is all from me. Thank you so much for listening to today's episode of Nudge. A massive, massive thank you to the godfather of influence, right, Robert Cialdini for coming back on the show. And I'll be back next Monday with another episode. Bye bye.