Another anecdote for the “Springs Be Scary” list, I was helping my brother in law put theirs up two years ago, and similarly had trouble with the last spring.

We were using the tool included in the packaging, a little T post handle with a small hook on the end, sort of like one of those livestock processing hooks they use to grab heavy things with, just a lot smaller. And not sharp.

Well the last spring was being pulled back when the metal hook broke out of the handle, and shot into the nearby house window and broke one of the bottom panes.

Nobody was hurt, but with all the kids excitedly sprinting around, that metal bit was flying at eye level to 3 or 4 of them… Someone could have lost an eye.

Springs under load are scary as fuck, ask any garage door tech.