Mission Impossible, the first remake with Tom Cruise. The final scene ruined the whole thing for me. He’s hanging on the outside of a helicopter flying through a train tunnel chasing a train - which apparently wasn’t improbable enough because he then blows up the helicopter and the explosion sends him flying safely onto the train.
I’m sorry, but that helicopter was made of metal and glass. Anything that blew it up is going to turn him into a fine mist. In another, cheesier action movie, fine! But the movie took itself so seriously otherwise that I just couldn’t anymore.

It’s anecdotal, but I was bullied mercilessly when I was a big, fat sixth grader by this pack of fifth graders who would run up behind me during lunchtime in the playground, kick me, and run away. This went on for some time until one day I happened to turn around at just the right second and caught this little shit by the name of Cory Rodgerson.
I took a big, wide swing and smacked him upside the head as hard as I could. One punch. I vividly remember (probably partly falsely given the forty years that have passed) him spinning, falling over, and then bawling his eyes out. I felt horrible about it, but you know what? Him and his group of cronies never bullied me again.
He learned that actions have consequences, and I learned that violence sucks, but sometimes it does solve problems. Was there a better solution? Probably, but telling my teachers and parents had had no effect, so what else was I supposed to do about it? I also did not grow up to be violent, and in fact have never gotten into any kind of physical altercation as an adult, so maybe it was a good lesson for me, too.