What Trust is Made of

Some years ago I was hired by France Telecom to investigate the factors influencing trust between trading parties in online marketplaces. The caveat was that in those distant days there was no established marketplace to be studied. I therefore began my research by conducting qualitative interviews with France Telecom targeted audience, small business owners, providers of advertising services including radio stations, print shops and local newspapers. This was 2002 after all.

What came out of that work is a very simple diagram that I found myself drawing and presenting frequently over the years to explain how most of us operate to decide whether to trust perfect strangers within the context of a transaction. This theory informed the Design and Information architecture of product cards and detailed records particularly in the e-commerce space. Here is that diagram:


The less you know about a product or service, the more you tend to rely on subjective criteria to assess it

The less you know about what you are acquiring the more you tend to rely on subjective criteria.

Here is an example I frequently use to illustrate this point:

“Pretend that you have just moved to a new city and are looking for an auto mechanic to fix a problem with your car. Assume that you know nothing about car repair. You are now standing in front of a mechanician at his shop and are trying to determine whether you are going to entrust him with fixing your beloved car. What are you going to base your decision on?”

When presented with this scenario, a majority of folks will evoke the mechanic’s “friendliness” and “demeanor”, his “trustability”, the overall aspect of the garage, its “cleanliness” and maybe how the matter of the cost of the repairs is presented. All elements that are immediately available, mostly subjective, and at best, remotely representative of the mechanic’s expertise and skills. To use concepts recently popularized by Daniel Kahneman, we fall victim to the Substitution bias. When unable to answer a question for which we have little to no information, we instead elect to answer an adjacent question for which we have a ready answer. In the above example we substitute “Is this a skilled mechanic?” with “Is this a friendly and tidy person?”.

Conversely, the greater your expertise with the service or product you are assessing, the more likely you are to focus on objective criteria.

Several fictitious examples easily come to mind to illustrate this behavior but you can also reminisce of a situation where you assessed something you are expert at, maybe in a professional setting, and how you focused on clear data points. I personally like to borrow a scene from a favorite movie of mine, the Good, the Bad and the Ugly by Sergio Leone, called “Tuco at the gun shop”. As the title suggests, the scene shows Tuco acquiring a new gun by going through a rigorous evaluation of the weapon’s key components. He verifies the straightness of the barrel, tests the cylinder’s ratchet, inspects the cylinder flutes and concludes with target practice. The shopkeeper is not consulted at any moment, shinier weapons are unceremoniously dismissed, Tuco gives all the appearances of a gun expert who relies on objective data points to drive his purchase decision.

Misplaced Trust

As you begin playing with this theory and applying it to different scenarios you might realize that it is more accurate to consider Trust in association with its object, in other words: “What are you placing your trust in?”. Here again there a simple diagram I found helpful.


Would you trust yourself to assess a product or would you rely on the salesperson?

Applied to the auto mechanic example You trusted yourself to assess the Purveyor of the service. What were the other options? You could have placed the burden of making a decision on the shoulders of a car enthusiast friend. Effectively swapping your friend for yourself in the above diagram. Naturally our first theory still applies to your friend. Instead of your friend you could have also relied on online reviews, thus crowdsourcing the trust decision.

Regardless of who performs the assessment, another possibility would have been to shift your focus from the Purveyor (the mechanic) to the Object(the service) by asking to inspect repairs in progress and ask questions about them (the equivalent of a portfolio review in the design world). One will note that in this example Object and Purveyor are one and the same for the mechanic is both the salesperson and the service you wish to purchase.

In the Good, the Bad and the Ugly, Tuco trusted himself to directly assess the gun he sought to acquire (the Object of the transaction). The Purveyor was ignored. It is worth mentioning that Brands also act as Purveyors, in effect they play the same role as a salesperson by telling you: “Trust me, my brand is a seal of quality and vouches for the product”.

But how is this relevant to Product Design?

I have found that combined, these two theories are especially handy when working on sites that feature products or services whether from a transactional or informational perspective. A Designer working on how products and services are presented to the buyer in a marketplace might want to consider whether a persona’s purchase decision is most likely to be driven by subjective or objective criteria and how that may vary from product to product. An objective shopper will be more receptive to data sheets, technical specs and feature lists, while a subjective one might be more easily swayed by lifestyle attributes, staging or brand.