A term generally used by skateboarders when they land a trick on their first attempt.
It can be used in any scenario, not necessarily just skateboarding. For example, you could land a water bottle flip and say "first try.”

A massive dump that takes 10 to 15 times to flush.

In the context of Speedrunning, this is often said in a joking or sarcastic manner when a trick or other act takes more than one attempt.

What dude perfect says they do it on the 1,567,843rd and 1/2 time