[balves]

I think the only correct answer is "it depends"

It depends on the relationship with the person who's code you are reviewing, it depends on the relative seniority differences, it depends on the project, it depends on the rest of the team culture, it depends on the rest of the company culture, it depends on how long you've had a working relationship with this person, it depends on who else might see the review.

I've had working relationships with people where it was beneficial/easier to be super curt and to the point, because there was sufficient 2-sided trust that best interests were at heart. I've had working relationships where I had to take having "open-ended genuine curiosity" to the extreme because of fear of feelings being hurt.

That being said, by default I take a question-asking tone to the code review process, with the intention of possibly learning something. It opens up the door to "being wrong" and allowing things to progress without incessant arguing. There are times when this approach isn't appropriate, but I think it's a reasonable default. Again, it depends.