A go-around (lun) is complete when everyone has discarded once in turn (3.4.1); A hand (pan) is everything between a deal and either a declaration of "Hu" or nobody winning — a draw game (3.4.2); A round (quan) ends when everybody has been dealer once; there are four rounds in a complete game (3....
Why people argue about this
People often assume that a round in Mahjong MCR/WMO ends when one player wins by declaring "Hu," forgetting that there are four rounds total, each with its own dealer, regardless of who might have already won within those rounds. This confusion stems from the rule stating there are four rounds per game, not necessarily tied to individual winners or losers within those rounds.
