7. users do not always tell the truth
In an example from an interview we could see very well that respondents often tell small lies, not even intentionally. They don't want to badmouth a product or look "stupid" themselves because they don't understand something.
In the example interview, the respondent said that he can use the hearing aid very well and has a lot of practice with it. He also claimed, for example, that a display for the remote control is necessary and will not work without it. His wife was also in the interview. When it came to operating, he had serious problems and the wife had to help him. In general, his wife interfered a lot and said things like " darling, you know that " and put him under pressure. If he did not know something, she showed it to him. For the user himself, the operation was obviously too complicated. He also had to wear glasses to operate the display, because he couldn't read it without them.
If you now compare the mere statements with the observations, you notice that this does not agree absolutely. It is therefore important never to rely solely on statements, but to always conduct an interview in context and observe the user's actions.