A few comments.

Very rarely I get stuff that is so badly made, or naively implemented that I just have to say no, then go help the person redesign the solution. This happens rarely though, maybe twice a year with a fresh employee.

If the code is not formatted to the linter, it should not have been submitted for review and I will probably reject it. We have to hold our work to some kind of standard.

Otherwise I do the "I did not understand this, can you please explain?" Quite a bit if a part is confusing.

I try to invite to a discussion, not demand doing it to my taste and make it clear a lot of the comments are suggestions for future work.