One of the things I find myself asking middle school students is "What were you thinking?" That phrase seems innocuous, but it really about the context and the tone. For example, a student is designing a project for class and added and interesting aspect to the design. I sit next to them and ask "What were you thinking when you designed this?" and the student explains their thought process. The other end of the spectrum is a student who blurts out an off topic question and I respond, "What were you thinking?" and they stare blankly back without an explanation. In one instance, I am asking for more information on a thoughtful piece of student work and the other is an exasperated response to a student behavior. I have been teaching for over 20 years and I still expect the 2nd student to provide an answer even though I know they do not have one. Asking that question in that situation is a bad habit I have improved on, but will still continue to work on until it is eliminated from my frustrated teacher vocabulary.
Instead of asking that question, in any situation because of how students might have interacted with it in the past, there are some other ones that I use in place that allow for more conversation with the student.