I was LUCKY!!!
I am pretty retentive about watching & listening to my garage car lift and my boat lift during operation. Yesterday, a one year old UP limit switch failed. I noticed that my normal reference point (the top of the PVC guide post) was closer than normal to the boat house rafter. I was able to stop the lift before any contact/damage (with about 2" to spare).
Stay alert!
Tom

Yep - I always watch mine. Had one move on me one time and it was a ****show.....

A new switch did NOT resolve the issue...upon additional investigation we discovered that there was a nick in a wire that caused an intermittent failure.

My marina ONLY uses boat lifts (love it). but they had to stop using limit switches after too many failures. It means I have to stand and hold a button for an eternity while moving the boat. However they had multiple failures/issues.

Was there a bad storm that flooded the electronics on the lift? These rainy days are breaking all my stuff

In my case, it was most likely a nicked wire during installation/repair/maintenance that went unseen for years.