You are handed three things and asked which may be treated as established. In a research session a customer says she gave up looking for her renewal date and phoned instead. An executive says the product needs a dashboard. Analytics shows two in five sessions ending on the account page. How should each be classified?

The principle — classifying evidence by where it came from is the whole discipline, and it is done before anyone argues about what to build.

Why the key is correct — take them in turn. The research session gives a need, because ‘User needs’ are the needs that a user has of a service, and which that service must satisfy for the user to get the right outcome for them. and both halves are present: the need is of the service, and the outcome is knowing when the renewal falls due. The executive's dashboard is an assumption, because the instruction is to Treat any opinions or suggestions that do not come from users as assumptions that have to be proven by doing research. and an executive is not a user of the service. The analytics number is neither. It is an observation that something happens, and it will not say what those people were trying to do, whether they succeeded elsewhere, or whether ending on that page is a failure at all. Its job is to point research at a question, which is the sense in which If you do not understand who they are or what they need from your service, you cannot build the right thing. It may be treated as real and it may not be treated as explained.

Why the others are wrong — promoting the executive's view on the strength of seniority confuses who must be persuaded with what kind of claim has been made. Promoting the analytics because it agrees with the session lets corroboration change a thing's category, when all it does is make one interpretation more likely. And counting the number as a second need stretches the definition past a sentence that requires an outcome the user is trying to reach.

Remember this — need, assumption, observation: three categories, and the third one is a question rather than an answer.

Sources — the UK Government Digital Service Manual on learning about users and their needs.