In this movie they took them up in space. They're floating around and doing zero gravity stuff. Well, they had to do it all on wires. All the wires had to be painted black against this black background. If you didn't light it properly you could see the wires. Drove them crazy!
If you can react the same way to winning and losing, that's a big accomplishment. That quality is important because it stays with you the rest of your life, and there's going to be a life after tennis that's a lot longer than your tennis life.