1. Your web survey must allow respondents to go back to the previous answer or page of answers.
2. It must allow this without clearing all of the data they have already entered.
I am a researcher. I care about research in general. I care about the topic of the survey which prompted this post. It is important and also related to my own work. But when I tried to go back to change an answer on the previous page and all my responses were cleared, I just closed the browser tab containing the survey and do not plan to go back to it.
This makes me rather sad, because most people don’t have the time to deal with the consequences of someone else’s poor design decisions. Sigh.