Many players often make the mistake of discarding a card that might aid an opponent in finishing their melds. As a result, it's crucial to consider not just your hand but also the cards that have rummy funalready been played and those that are still drawn. Generally speaking, you should be careful about what you leave for your opponents & discard cards that are less likely to help your own melds. When it comes to discarding, timing is also essential. Holding onto a card for a few more turns is a good idea if you have a run or set-completing card but aren't sure if it will help you overall.