Many players are always looking for shots to put away, especially when serving. The problem here is that if you consciously look for shots to put away, then you are consciously taking control of your shots instead of letting your training (i.e. your subconscious) do what it's been trained to do. Instead, just let the shots happen, i.e. let your trained reflexes take over.
If there's a shot you can put away, your training should take over and you'll put the ball away. If it's not a shot you can put away, then your training will allow you to react appropriately – but if you were consciously looking for a ball to put away, then that won't happen as you've put aside your training to consciously take control. If your training doesn't take control properly, then you need to train yourself so that it does happen.
How do you train yourself to reflexively go for winners when the shot is there? Practice. (Pause while you stop groaning.) And how do you do that? Here are two ways.
- With a coach: He can feed you multiball where he mixes in difficult and easy shots, and you put away the easy ones. After each shot is when you consciously think about whether you went for the right shot. You can do this against either backspin or topspin, or a mixture.
- With a practice partner or coach, or in practice matches: Practice your serve and attack, where you have to judge each time if your partner's return can be put away or not. Try to clear your mind and let your reactions take over. After each rally, that's when you should consciously think about whether you went for the right shot. If you think about it, your subconscious will get the message.
When should you go for a put-away shot? That's different for everyone, but you'll learn what you can do with experience and practice. Obviously high balls should be put away, but you should also learn to put away most balls that land in the middle of the table (depth-wise), shots where you aren't rushed or pressured (by the ball's speed, spin, or placement), and perhaps even off a strong shot when you read and time the ball just right.