each serve has ~5% chance to touch the net. In a normal set where you serve 5 times (for a 6/4 scores), with an average of 6 points per game, and 60% 1st serves in, that'd give you about 42 serves, and thus ~2 nets / set. But it's an average, it can be 0 or 10 sometimes. If you have more points per game or/and less 1set serves in, then you'll do more serves and thus will have more nets.
When I tuned the net bounce, I did 10 or 20 serve games without a single net on serve, and same for the CPU...
== Mana Games ==
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