Some people just have a hard time killing a fish because there is ALWAYS a chance of it living. Back when I had 3 tinfoils, 4 commons and 2 fantails in a 20gal (yes noob then) My tinfoils beat the CRAP out of my calico fantail. His rear fin was GONE. All the way to his flesh and bone. Most of his other fins were gone to. I was 100% certain he was a goner so I let him be and expected to take him out in the morning dead. Well by chance of luck he DIDNT die, everything grew back 100% when he was only a few months old. Later that week I purchased a bigger tank and hes still kicking and becoming a massive beast over 2 years later.. Hes my little buddy now, and a big pig to boot. So some people I guess just hope that there is just this possibility of them surviving. I took that chance and couldnt have made a better one.