How To Build A Credible Site: Stickiness Part IV

Trust is perhaps the biggest barrier to closing a sale online. You can do everything right, but if your customer doesn’t have trust in you at the all important moment of buying, you won’t make a sale. With ideas it’s also important that people believe them. Your audience needs to trust that your message is true. Your idea needs to be credible before it will stick.

What the hell. Even I question my credibility

So far in this series on Stickiness we’ve covered the ideas of having a simple message, using the unexpected to attract attention and maintain interest, and using concrete details to make sure your ideas are understood. Today we’ll continue with credibility and how you can ensure your audience believes you and trusts your message.

As usual we’ll start with a quick review of the 6 Key Variables of Sticky Ideas (SUCCESs) as put forth by the Heath Brothers in their book Made to Stick.

  • Simplicity – find the core
  • Unexpected – surprise gets attention and mystery keeps it
  • Concreteness– use details to help people understand and remember
  • Credibility – help people believe
  • Emotion – make people care
  • Story – get people to act

If you haven’t read the previous posts in this series you may want to give them a read prior to reading this one as some of what we’ll be looking at here will make more sense in the context of the entire series.

The Incredible Hulk album cover


Credibility is about the believability of the source of a message or the message itself. Typically that means trusting messenger and/or message as well as seeing authority in either or both.

In order to get people to believe your idea you need to offer some source of credibility and there are 3 basic ways an idea can be seen as having signals of credibility.

  • A trusted source external to the idea says it’s true
  • The idea itself carries internal trust
  • The idea is testable and provable

Each of the above lends credibility to your idea and so can be used as a source. Ideally you’d have all 3, but any can work on its own. It’s not always obvious which will work best with your audience, which is why having more than one source is preferred.

External Credibility

When someone you trust or someone who’s an authority on a subject tells you something about that subject you tend to believe it. The trust you feel for that person is transferred to the idea. The authority he or she carries is given to the idea.

A sign with the word 'Trust'


We trust different people for different reasons.

  • Family and friends because of our long standing relationships with them
  • People who have previously made the decision we’re about to make because of their relevant experience
  • People who have little to gain by us believing them because they have nothing to gain

We know our family and friends and for the most part believe they are being honest with us. That might depend on who your family and friends are of course, but most of the time we’ll trust them to tell the truth. At the very least we know who among them to trust and who not to.

We’ve learned over time which of our friends and family we can believe.

When people have previously done what we’re about to do we trust their experience. They can offer us details we can’t yet know about our impending decision. Testimonials can be powerful in part for this reason.

People who have nothing to gain by our believing them are also believed. The fact that they have nothing to gain gives them no reason to lie to us and no reason not to trust them. Again testimonials come into play. In most cases it should make little difference to someone who’s bought a product whether or not we buy it as well.

Naturally with testimonials you may or may not see them as legitimate. If you suspect the seller as leaving a testimonial for his product you aren’t going to believe that testimonial. The profit motive has come into play. Or perhaps we see a complaint as someone with an axe to grind.

Social proof can be one way to generate external credibility. If 100,000 people already subscribe to a blog it’s probably worth subscribing to. You might see content ranking well in search engines as more credible seeing it either as social proof or as an authority (the search engine) vouching for the content.

There’s something of proof in numbers. If many, many people are telling you something is true you’re more likely to believe it than if one person were telling you it’s true.

Other external sources of trust we can add to websites include the logos of trusted sites and various trust seals from security companies. Links into our sites may be seen as trusted recommendations depending on how you feel about the site linking in. More comments on our blogs display social proof can work as well.

Detail from the side of a D. C. Housing Authority Police Department car


Authorities are usually people with expertise in a subject. You’ll likely trust your plumber to tell you information about the pipes running under your sink. You trust your doctor about your health. Authority can trump trust.

While I trust many of my friends, none are experts in nuclear physics. I might trust them to point me to a source on nuclear physics, but wouldn’t believe their advice on how to split an atom without an outside source corroborating.

Ideally you want to be seen as an authority on your subject so when you have an idea or message to convey your authority status alone can lend credibility to the idea. External credibility means external to the idea and not external to the messenger of that idea. You are external to your ideas and authority you’ve built up on a general subject can be transferred to specific ideas about that subject.

Failing authority status on your own you’d want to get someone who is seen as an authority to confirm or validate your idea. Similarly if you can build a trusting relationship with an audience it’s more likely that audience will believe your message. And again should you not have built that trusting relationship yet, you’d want to find someone else your audience trusts to validate your idea.

One reason many business will choose to start a blog is to build a source of external credibility. Over time you can show your knowledge about a subject and build authority for yourself. You also get to build a trusting relationship with your audience over time. A blog done well can be a great way to set you up as a credible source for your later ideas.

When it comes to the design of your site it’s likely that a professional looking design will carry more credibility than an amateur one. By designing based on sound and proven principles an audience is more likely to see you as an authority.

Naturally that would be true if you’re a designer, but it’s also true no matter what business you’re in. An unprofessional site sends a message your business isn’t to be trusted. It sends a message that you don’t care enough about your site so why would you take care of your customers. It’s similar to the difference of having a store in prime real estate and selling your merchandise on portable stand on the street.

Internal Credibility

We won’t always have an authority or trusted source at hand to verify our claims and we may not have yet built a trusting relationship with our audience. It’s possible you may be seen as having something to gain with your idea losing some credibility due to that potential for gain.

Fortunately your idea itself can carry some credibility on its own. Your idea can have internal credibility. In fact we talked about one way last week.

A green fly next to the word 'details'

Details Are Believable

Concrete details are more believable than abstract concepts. Concrete details make an idea seem more tangible and more real, thus the idea becomes more believable.

Vivid details boost credibility.

It’s why case studies (PDF) can be so powerful. It’s also why the the most aesthetically pleasing designs are the ones that add a detailed touch. It’s why the most usable designs are those that get the small details right. Sweat the details and put in that extra effort to get them right and you gain credibility

However the details should reinforce, symbolize, and support the core idea. They need to be in harmony with it. They need to be truthful to the core message you’re trying to convey. Adding details for the sake of detail is not what we’re looking for. Adding detail that supports the idea is.

Pie chart showing compostion of Britney Spears

Statistics Offer Proof

A second way to generate internal credibility is the use of statistics. Statistics come across as evidence.

Statistics carry one problem though. We don’t want to study them and numbers by themselves often have no meaning without context or without relationships to other numbers we have a context for.

When we talked about concreteness I offered an example of movie popcorn being unhealthy due to it containing 37 grams of saturated fat. To most people that’s meaningless. How much fat is 37 grams? Is that good or bad? We could more easily see it was a lot of fat when we saw it was the same as in a bacon and egg breakfast, a Big Mac and fries for lunch, and a steak dinner with all the trimmings—combined.

Statistics will work best at boosting credibility when they illustrate a relationship to something known. They work better when you make the statistics meaningful.

Credibility is also improved when statistics can be placed in more human terms. Again think of the movie popcorn example. The human terms are the breakfast, lunch, and dinner it was compared to. You may not know how much 37 grams is, but you do know how much all that food is.

If you can equate statistics on a human scale and make the data meaningful (PDF) they’ll be understood more and as a result lend credible proof to your idea.

Can Your Idea Pass the Sinatra Test?

A third way to build internal credibility is the Sinatra Test. Recall the song New York, New York.

“If I can make it there, I’ll make it anywhere.”

You pass the Sinatra test when a single example is enough to prove the rest. In the song making it in New York is proof you can make it in Chicago or New Orleans or Milan or Shanghai.

One way to pass the Sinatra test is by having that one super client you’ve done work for. Say Apple let you design their latest site. Even if they never give you a recommendation or testimonial you can point to the site. If you’re good enough to design Apple’s site you’re probably good enough to design mine as well.

This is the idea behind test cases and portfolios. Your clients may not be as big or have the design sense of Apple, but they might help you pass the Sinatra test.

Having written for the New York Times or Washington Post you can probably be trusted to write for the local Penny Saver. Climbing Mount Everest would surely mean you could climb any of the many other mountains around the world.

Test questions for the Real Estate Investing College

Testable Credibility

Perhaps the most powerful form of credibility is testable credentials. If people can test your ideas for themselves and draw the same conclusion as your idea, it’s instant credibility.

Are You Better Off Now?

In the 1980 U.S. Presidential election Ronald Reagan asked voters to ask themselves if they were better off than they were 4 years earlier when Jimmy Carter took office. Instead of pointing to statistics about the economy which would have shown most people weren’t better off, he simply asked them to make the determination for themselves.

It was obvious to most people that they weren’t better off. It was a testable credential. It let voters prove to themselves the conclusion Reagan wanted them to draw.

Testable credentials throw the burden of proof back at your audience. A visitor to your site likely sees themselves as the most credible source. Get them to prove to themselves that your idea is credible and they’ll see it as credible.

Where’s the Beef?

If you’re old enough to remember the 1980 election, you should also remember the Wendy’s “Where’s the beef?” commercials. If you don’t you can watch the commercial above.

Three elderly women are at the counter of a fast food restaurant looking at what appears to be a very larger hamburger. The dialog between two of the women is as follows

“It certainly is a big bun”

“A vey big bun”

“A big fluffy bun”

“A very big fluffy bun”

Then there’s a pause until one woman lifts the bun to reveal a tiny burger. The third woman asks loudly, “Where’s the beef?”

Wendy’s threw the proof back to you. They did have a larger burger at the time and if you compared a Wendy’s burger to one at McDonald’s or Burger King, the Wendy’s burger was the biggest. That was the testable credibility. Anyone could see it for themselves and prove it to themselves. You can’t beat credibility you can see with your own eyes.

If you’re a web designer your portfolio and your site can stand as testable credibility. Others might do well with free demos, a free chapter of a book, a money back guarantee. These let people see for themselves your claims about your product are real.

Abraham Lincoln reading to a boy


What makes someone believe you? The answer is to provide one or more sources of credibility. That source could be an external authority, internal details, or something testable, but you need to find a source to make your idea credible in the mind of your audience.

External credibility borrows the credibility of the external source. Internal credibility relies on concrete details and meaningful statistics, or by passing the Sinatra Test. Testable credibility is the strongest form of credibility as the proof falls on the audience. If someone can prove to his or her self that your idea is credible there’s no room to doubt it.

With trust being such an important part of doing business online keep the ideas in this post in mind not just when trying to create a sticky idea. Keep them in mind for everything you do as part of your business.

Next week we’ll continue our look at sticky ideas by looking at how we can make your audience care about your idea. We’ll talk about the power of emotion and how making an emotional connection between your idea and audience will make them excited about your idea.

Frank Sinatra painted on a brick wall

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  1. I think credibility is one of the most important aspect to consider to build a goo site. In particular in the web there are many people and many sites or projects that are not serious and reliable. Nowadays to be credible and to make people to believe us is foundamental, infact what is credible is good otherwise what is hazy or not proven is bad. The difficulty consist in how to build a credible site, a sticky one, but your advice are really useful!! Thanks for sharing!

    • Thanks Tad. Yep I did mean credible. My fingers sometimes type what they want instead of what I’m thinking. Bad of me not to notice before publishing though in my defense I’m on vacation at the moment and not as observant as I should be. 🙂

      By the way thanks for the tweet. Much appreciated.

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