I would like to take a moment to say thank you to Jeff Cavaliere for posting this great video as he NAILS these right on the head. It isn't often that I agree with everything a fellow fitness fanatic says, but I gotta say, I am sure glad this guy took the time to put together this video of the top worst exercises. It's my belief that all exercises have a value and that MOST of the time, the issue people have with not getting the results they want from any given exercise, is that they have somehow misaligned the exercise with their capabilities/goals.
Sadly, with the exercise Jeff talks about in the video, most people aren't going to get the benefit they think they will, but rather, they end up increasing injury opportunity. Jeff does a great job pointing out some exercises that are more likely to cause injury than to yield safe progress, like the behind the neck press, so watch the whole video.
Just a little self-deprecation side note: I have been guilty of doing a few of these myself in the past for the wrong reasons and have caused myself some shoulder wear and tear that I wish I hadn't. I am by no means immune to making mistakes and I am glad I finally learned a better way to go about getting the results I wanted.