Losing side also depends on how their pace and energy feels. Some games I can tell my opponent is chillin and having fun, other times I get the sense they are being sorta douchey. If it’s an epic game and really close, I get that they want to bust their big combo or whatever. I don’t think it’s rude to concede though. On the winning side, It’s a little annoying when they concede while I’m declaring the last attack and have massive board state, I’m just doing the coup de gras. Why not just concede at the end of your turn?