The endgame (and really the whole point) of a sale is for your prospect to say, “yes”.

We’ve talked a lot about having a process and what actions you can take to increase the chances you get a “yes”. But how else can you persuade your prospects to buy what you’re selling?

I love psychology and the whole topic of persuasion and the psychology behind it is incredibly fascinating.

So, how you can use the psychology of persuasion (ethically of course) to up your closure rate?

Psychologist Robert Cialdini, considered the father of the psychology of persuasion, identified six principles that significantly increase your chances of getting a “yes”.

These are reciprocity, scarcity, authority, consistency, liking and social proof.

Let’s have a look at the first three and how you can use each to boost your sales.

1. Reciprocity

If someone gives you something – whether it is a gift or service – there is an unspoken obligation for you to return the behaviour.

Basically, if you’re prospect feels that they owe you then they are more likely to say “yes”.

To demonstrate the power of reciprocity, Cialdini uses an example from a series of studies which looked at what influenced the sizes of tips the waiter or waitress received.

If the waiter gave diners one mint once they’d finished eating, then tips were about 3% higher than normal. Two mints didn’t just double the percentage increase – it more than quadrupled it (14%).

What made the biggest increase was when the waiter gave one mint, walked away from the table before stopping, turning back and saying, “For you nice people, here’s an extra mint.”

Tips increased by 23%!

Cialdini identified that it wasn’t what was given but how the person gave the gift that influenced its effectiveness.

Now, how can you use this in sales?

If you’ve done a good job of developing a relationship with your prospect and understand their challenges, you’re in a great position to identify what you can do for them before they do anything for you – i.e. buy your product or service.

The key is to give them something that is personalised, and they won’t expect.

Add value upfront and your prospect is much more likely to return the favour by saying, “yes”.

2. Scarcity

This principle is used everywhere.

“Get in quick”, “Offer valid until”, “Last chance,” “Limited spaces available,” “Buy before X date and receive…”

And it’s used because it works. Even though you’re probably pretty aware of it when it’s done to you, it can be hard to say no.

It plays to people’s fear of missing out (FOMO!).

As soon as people think an opportunity is being taken away, they want it more.

A great example is New Coke. In 1985 and losing market share to sweeter alternatives, such as Pepsi, Coco-Cola decided to reformulate their recipe and released New Coke.

It didn’t go down well with a massive public outcry demanding the return of the original Classic Coke.

Interestingly enough Gay Mullins, one of the loudest voices for reintroducing the old recipe, who formed the Old Cola Drinkers of America,either could not distinguish or preferred the flavour of New Coke on blind taste tests.

So, despite New Coke tasting better than Classic Coke, the demand for the return of the original recipe was fuelled by its scarcity.

In fact, a psychiatrist who listened to calls of people complaining to Coca-Cola said that some of the callers sounded like they were talking about a death in the family!

There are many business lessons from the New Coke debacle. When it comes to persuasion and sales, helping your prospect understand what they could miss out on or stand to lose is incredibly powerful.

Most sales pitches involve talking about the benefits of your solution but also make sure you also discuss how things will be if they don’t solve the current problem.

A good way to do this is to just ask them – “what is the impact if you don’t do anything about problem X now?”

Like the examples at the start of this section, the scarcity principle can be used to help close the deal.

3. Authority

If you think someone is knowledgeable and credible, you’re more likely to do what they say.

A simple and effective example is the real estate agency that had their receptionist introduce each agent with their experience and expertise before putting the call through.

For example, “Let me pass you on to Mary, who has 17 years’ experience selling houses in your area.”

The result was a 20% increase in appointments and 15% more signed contracts.

The principle of authority is why referrals and testimonials work so well if they’ve come from someone your prospect thinks is knowledgeable and credible.

Importantly, you need someone else to set you up as an authority in your area, as the receptionist did for their colleagues. You can’t do it yourself!

Think about what companies and people that you and your organisation have worked with or use your solutions, who will portray you as knowledgeable and credible in your prospect’s eyes.


You can ethically use the psychology of persuasion to make sales.

Reciprocity can create an obligation where your prospects are compelled to say “yes” to your products or services. Scarcity can encourage them to make their decision faster and get them across the line. While authority sets you up as a knowledgeable and credible person who can help them solve their problem.

We work with business owners and salespeople to help them attain and close more sales. Get in touch to find out more about our sales training and coaching programs. Get in touch


Sharn Piper – CEO
M: +64 27 733 4333