If I display the results of a form with optional questions and some are unanswered, should I show them?
I have a page that is editable with informations about clients. It shows the questions that are answered, but not the ones unanswered. Should I show them, or is it okay to see those questions only while I'm editing the infos of the page? There is a place on the page that shows how many unanswered questions are lefts. They appears on click.
Yes, you should show them.
In the review stage, the user should be presented with their complete responses. In the case of an optional question, providing no answer is the response they have chosen, so that should be what they see when reviewing.
This provides the user an opportunity to confirm that they really wanted to skip answering the question, which increases the chance that they submit the form as they intended.