It sounds simple -- it is. Most of us play outdoors. There is no ceiling. Therefore, to be competitive, keep the ball out of the net. If you make an error, make it by hitting the ball long or wide. This way you give your opponent a chance, at least, to play an out ball. Many times when I watch a match I see my students play an out ball. It may not be out by much or it may be out six inches. In the heat of the point many players play out balls. This never happens when your opponent makes the error in the net.
How many times have you been caught in a bad position during a point, like no-man's land, and you play a ball that as soon as you hit it you realize it was going out? That is another reason why you should keep your shots out of the net.
If you trust the "law of averages" and you keep your shots out of the net, you will be the benefactor of many bad judgments by your opponents.
Good luck on the courts!