I agree. My preferred phrasing uses “we” (we are working on this code together) instead of “you” (you are working on this code and I am telling you off) and is usually a sort of polite suggestion with concrete justification. For example:

Another thread could have modified ‘x’ between when we test the condition and when we take the lock, so we should test that ‘x’ is ‘NULL’ if ‘y’ is true here, and if not, sleep and retry.