In at least one recent TU application, there was not a single criticism or negative remark during the discussion period and yet there was still a "no" vote in the result. A "no" vote is an objection and it is important to bring it up during the discussion period so that other TUs may take it into consideration when voting. It also gives the candidate the opportunity to address it, which itself can be very informative during the discussion period.
I am not trying to call anyone out. It may well be the case that someone missed the discussion period or misclicked while voting, or has a personal objection or a blood vendetta against the candidate's family spanning back 5 generations that they are not allowed to talk about. I absolutely do not want to know who voted "no" or why. I just want to encourage everyone to participate in the discussion period when they have something to add.