Trusted by 300000 salespeople
Every marketer knows that social proof – showing that other people use your product, support your cause, etc. – is a powerful persuasion tool. It’s one of influence expert Robert Cialdini‘s six main principles, and may be the best-known and most-used of them all. But not all uses of social proof are equally effective.

After reading an enthusiastic review of Yesware by fellow Forbes contributor Alexander Taub, I decided to take a closer look. Yesware is a sales software plugin for Gmail, and has apparently achieved some level of traction.

When web visitors are pondering whether to download a product, showing that “everyone is doing it” is one key way to increase conversion. Even free products (or freemium-model products) encounter resistance. There’s always a chance the product will prove to be useless, or, even worse, will somehow cause problems with the user’s software or hardware. To build confidence, Yesware uses the illustrated odometer-style graphic showing that the product is “Trusted by 300,000 Salespeople.”

That’s an impressive number, and should encourage on-the-fence visitors. I like the use of “trusted” – not only does it emphasize trust (these guys won’t break my mail program or steal my contacts), but it finesses the difference between downloads and active users.

Where this social proof effort goes wrong is the counter-type display with an extremely round number. Research shows that precise numbers tend to be more believable – see Precise Pricing Pays Off, for example. The counter with a perfectly round number like 300,000 lacks precision and looks improbable. The visitor’s non-conscious doubt may be increased by the very precision one expects from an odometer – when was the last time you saw an odometer reading ending in five zeros?

I’m sure that including the 300K number, even presented as they do, causes a higher conversion rate than no number at all. But, I’d test these options against the current design and see if any converted even better:

Good: Lose the counter display, and go with prominent text: “Trusted by more than 300,000 salespeople!” While not precise, this avoids the counter imprecision issue and has the positive implication that a major milestone has been passed.

Better: Keep the counter, and update it daily, or every few days, with the actual number, e.g. “Trusted by 305,226 salespeople!” Now, the counter looks plausible and precise – exactly the reason why you’d use that font instead of traditional type.

Best: Keep the counter and make it dynamic. Either update it in real time, or, if that’s impossible, calculate the average rate of change and use a simple script to increment the count after a specific number of seconds. This has the advantages of the “Better” approach and offers even stronger social proof with its motion.

As any conversion expert would tell you, of course, my suggestions are hypotheses to be tested rather than 100% certain CRO boosters. But, I’d be surprised if at least one didn’t beat the current page design.

Do you use customer counts on your website? Have you found a way to use them that works best? Share your experience in a comment!