Many players reflexively reach for the ball when caught out of position. This means leaning toward the ball, with your weight on the foot in the direction you are trying to move - and so you can no longer move in that direction! And so, rather than move into position you are forced to lunge for the ball. If you'd instead stepped, you would be in a much better position to make a good shot. This is a fundamental problem that should be fixed. Instead, the first reflex should be to step to the ball, while staying balanced. Reaching should only happen as a last resort. (Stepping includes shuffling so both of your feet move together.)
The only "good" lunging is after you have already stepped to the ball, and still cannot reach it. (It means you were truly caught out of position, a separate problem you might want to address.)
One way to practice this is to imagine a loose-fitting hat on your head, or actually wear one. Try to move without the hat falling off. This forces you to stay balanced as you move to the ball rather than lunge. And then, if you still can't get to the ball, only then should you make a last-second lunge as your hat falls off.