For a more detailed look at feedback read this great article from Dylan Wiliam called The Secret of Effective Feedback.

"But as many studies have shown, students often learn less when teachers provide feedback than they do when the teacher writes nothing (Kluger & DeNisi, 1996). The apparently simple process of looking at student work and then giving useful feedback turns out to be much more difficult than most people imagine. We could make the whole process considerably more effective by understanding one central idea: The only important thing about feedback is what students do with it." Dylan Wiliam 2016