To obtain an advantage over their opponents in a game of rummy, players must be aware of their patterns & tendencies. Players can make better decisions about which cards to pick up and discard, as well as gain insight into which sets & runs are likely to be new slots open at regular intervalsavailable for them to form, by identifying and taking advantage of their opponent's patterns. Keeping an eye on the cards your opponents are pulling from the draw and discard piles is a useful tactic for spotting their patterns. You can learn a lot about the sets and runs they might be trying to form by keeping track of the cards they are picking up. It also gives you an idea of which cards are still in play and which ones are probably available for you to pick up if you observe which cards they are selecting.