With some games you see the same problems happen again and again.
Bally Vector had a post that protected the ramp entrance, but instead of being machine threaded with a nut or T-nut on the back of the playfield, it was simply threaded into the wood. Because this post was a direct shot from the flippers, it never took long for it to break off.
Once the post was gone, the ball would then damage the entrance to the ramp, and eventually break off the mounting bracket.
As a bonus, the loose guide then chewed up the playfield.
Many games have the same kind of brackets, so you can apply this guide to just about any brand of pin.
Here you can see the repeted ball impacts have broken the tab off of the mounting bracket.