(N•ice Han•ds)
This is an expression used when someone makes a mistake usually with their hands. It can even go as far as them accidentally breaking something, falling, or any another accidental mistake where they may not even be using their hands. Really just a sarcastic ass remark following someone's mistake.
Here comes our waitress with a tray full of drinks. OH NO! She just dropped them all over the table. Damn! NICE HANDS! Now get us a towel!
In the world of Poker...
A lot of people think "nice hand" means well played. But they would say well played if they meant well played. "Nice hand" actually refers to the player relying on nothing but their hand to win the pot. Referring to the outcome as pure luck and not their skills that won him the pot.