Does it mean you are doing this operation enough times to trick the kernel to cache everything in RAM? Or you run it 3 times and chose the fastest timings?
I think there are sometimes arguments to be made that, for the user, that is run time. When using benchmarks to compare programs like this, though, I think isolating the "actual" (i.e. useful) program execution is productive.
Second run: fcp binary is cached by the OS in RAM so it starts up faster.
Third run: just to make sure :)
This is just one of the things of a type of cache that can be warmed up.