One was rejected simply because that journal had too large a backlog to handle new submissions. One journal didn't like the authors title and published it after the author agreed to change the title. There are a couple of cases where a journal said the topic wasn't really relevant to their journal, and the work then went on to get published in more relevant journal. In one case they said we like your work and think you're on to something, but your conclusion is too strongly worded given the data you presented.
In no case did the journal or reviewer state that they thought the paper or research was straight up wrong.
If I'm just one peripheral person on a long list I might read quickly through and say "Looks fine to me." But if I'm really reviewing something, I almost feel that I'm expected to at least find some nit-picks--as well as anything really substantial of course. It's pretty rare that I will be "No comments" on a first-pass review.
This is something you see all the time. Someone does a limited experiment, gets the result they where hoping for, and then get super excited and carried away and claim that their entire thesis has been proven true. I've rejected (or rather sent back for extensive revision) papers myself based on this, even when my gut feeling was that their conclusion was probably correct. Often the paper comes back with a more moderated conclusion and then gets published without a problem.