Originally Posted by TPC
It's not the dealers responsiblity
That is exactly what the dealer gets paid for, and is 100% their responsibility that the pot gets pushed to the correct player. If all cards are face up, it doesn't matter if you know if you have the best hand or not, it goes to where the best hand is.
If a player doesn't know that they're good, and puts their cards face down in the middle of the table it is the dealers responsibility to put that hand in the muck and not turn it over.
These two facts make it imperative, no matter what, if you go to a showdown in a live game FLIP YOUR HAND OVER. The hand at showdown can be asked to be seen by any other player that got delt cards that hand, so you might as well just show your hand. I've seen many people that have not shown their cards and latter claim they had the best hand....to bad. There's no shame in showing your hand, and if you're embarrassed then maybe you should have played the hand differently.