Most hooks will rust away. Some will come out, depending on where they are hooked. Some could cause the fish to not be able to eat and the fish could actually starve to death. The good thing with a LM is that the skin around their mouth is thin and rips easily. If hooked there, sometimes you will see the fish jumping trying to get the lure off, even after you break off. Which brings me to a funny story. I was fishing the rocks near a dam and had a short smallie hit my tiny crankbait. I was using ultralight line so it did not take much to break off. That little fish must have jumped for 15 minutes trying to get the lure out of his mouth. The crank bait had a rattle inside it, so you could always hear him jumping. I guess he knew he was now very vulnerable to big fish since he rattled everywhere he went. Kind of amusing.