I've still got a healing cut from a week or so ago. I have a cheap Chinese folder that I keep around as a beater (not because it's strong...it's not, but because I don't care if it falls apart). I was cutting up some boxes for spare bits of cardboard. I'm not really sure what happened, but one second I was cutting normally and the next the tip was cutting into my palm and the knife was shutting mid-cut. The liner lock is pretty thin and easy to disengage, so it was probably only a matter of time. Luckily, the cut was shallow so I only had to deal with a little plain.
Safe to say I'll be retiring that knife.
I have a knife like that, an assisted opening El Cheapo from China. $10 piece of crap. I cut and ground the heck out of that blade and don't trust the lock on the knife, as there is just too much looseness, starting with the overly thick spacers and general flex of it. So, I use it for general cutting as a beater, but am careful to not stress it too much. Not planning on opening cans with power jabs, like I do with my Cold Steel Mini Lawman. If El Cheapo cuts me, it won't be pretty.