system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How do clay tennis courts stay flat?

I have been watching lots of tennis videos lately, and I have always been curious how the heck clay courts stay flat after so much use. Even after just 1 match, I'd expect the surface to be full of divots where players ran, and where the ball hits the surface. If you've ever played tennis on an old court, you'll know that even the slightest deformations can cause the ball to bounce all over the place. It seems like this would be an issue for consistency, but it never is. Why is this?
gpt
The clay is compacted hard before it is playable. This is needed to allow the ball to bounce and to give the players grip on the clay surface. If you do not compact the ground then a lot of the energy in the ball will be used to deform the clay to create divots rather then to make the ball bounce up again. And it would be very hard for the players to get traction when they kick off to get to where the ball ends up. The compacted clay surface does stay together for several matches, likely for an entire tournament. If there is some unevenness in the surface then it is equal for both players and they can use it to their advantage or disadvantage.