I think a big factor of that is that usually most people just do the positive feedback and don't say anything negative or constructive. So when someone does do

I think a big factor of that is that usually most people just do the positive feedback and don't say anything negative or constructive. So when someone does do so, it's seen as "wow, this must be so bad that they just had to say something, no matter how delicately or toned-down it is being phrased as". These days I just mention the problems and concerns to the people making the decisions because yearly review time is the wrong time to do it. At best they've only been doing this "bad" thing for a month or so, and at worst almost a whole year and no one did anything.