I suspect we are all pretty familiar with this, although I think many of us, including me, struggle with the formative vs summative aspect. This can be ameliorated with increasing expectations over the semester, but that necessitates arranging expected work in small pieces. Portfolios are one way to organize expectations to help maximize the feedback aspect of evaluation. If one emphasizes summative formation, the formative aspect will be compromised. An example most of us can identify with is a visit from a supervisor who is going to give feedback on performance to help improve performance, but whose notes will also be used to determine merit pay.
Criticism is as likely to result in argument as reflection.
If a teacher emphasizes evaluation as determination of a grade as opposed to feedback, learners are more likely to treat getting a good grade, as opposed to learning, as their goal for the course. As I sometimes note to my class, good students are generally good at not letting a teacher know what they don't know. This is not ideal for learning.