Playing a game a few time as testperson might be fun,
but dont underestimate professional Playtesting. This is a really hard job, wich
I would not like to do.

Its not that they play polished and fun games, but mostly quite ugly and buggy -work in progress-
levels.

Playing a level 30 times, with every combination and unexpected movements, to find bug,
then marking down every little flaw ---- this is not Fun, but a hard job.

Then doing the same after the next bigger update...

Creating a game is more fun, than testing it in detail times and times again.