I had an accordion incident maybe 6 months or so ago.
It was a Strive leg press where you can adjust the thing so as to change the resistance curve. For leg presses I set it for maximum resistance at the top of the movement.
For some reason – it must have at least been after doing squats so it wasn’t a matter of doing it cold – I went straight to the machine’s maximum weight for the first set. It is a light duty machine so that is nothing impressive: 720 on the bars and then another 180 piled on top of the sled.
Felt fine lifting it off the stops. Really easy, even.
But as I lowered it, quickly it began to seem remarkably heavy and then suddenly it accelerated! SQUISH!!! I was completely folded up.
I was so surprised by the weirdness of what was going on that the reflexive response was, believe it or not, not to push yet harder (I wouldn’t at all be surprised if it could have stopped with max effort) but actually to stop pushing entirely or at least mostly. So the final part of the drop was REALLY fast.
The adjustment handle was of course in the “heaviest at bottom” position.
And the final-backup stops (if they can be called that) on that machine are low enough to allow Mini-Me a full ROM. It really was lucky that I wasn’t hurt on that bonehead move.