Knowledge transference. Developers are smart people, smart people want to know more, reviews are a way to spread that knowledge around.
At my last position we had a team agreement that no PR will sit for more than 24 hours without being viewed and no more than 48 hours (not counting weekends) without an approve/decline.
Myself, I would do PR's after lunch and at the end of the day. At this temp reviews would last no more than 15 minutes and would not be pressured.
YMMV, the important part is the team agreement.
I think the 24-48 hours agreement is pretty reasonable.
15 minutes review is a great achievement and hopefully it leads people to open short and manageable PRs.
I totally agree, team agreement is vital here.
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