Through observing which cards are being discarded most often, players can learn about their opponents' tactics and modify their own play accordingly. For instance, if you observe that an opponent routinelygmat slots discards particular ranks or suits, it might mean that they are not attempting those melds, which would free you up to concentrate on those areas. Also, players can make well-informed decisions about which cards to pick up or discard by keeping track of the discard pile. If a card has been discarded several times without being picked up, it might indicate that other players don't think much of it either.