An opponent may be attempting to form particular sets or sequences if you observe that they routinely select particular suits or ranks from the discard pile. It might be prudent to refrain slots in motherboardfrom throwing away cards that could help them finish their melds in these situations. As an alternative, concentrate on improving your own hand while discarding cards that are unlikely to help anyone else. In Gold Rummy, maximizing point opportunities entails both tactical hand management during the game & creating legitimate sets and sequences. Every card has a point value.
