How many say aeroplanes do you think the average airline pilot crashes during training? A few dozen? Maybe only a handful of big jets with passengers on them because presumably you'd practice stuff like "Not smashing an airliner full of people into a mountain" last?
No. We don't learn to fly aeroplanes this way because it'd be stupid. Aeroplane pilots learn from other people's mistakes instead. Even when they have an accident and they personally learn from that, every effort is made to also teach other pilots who didn't have the accident the same lessons. A guy will stand up and lecture other pilots about the time he did an Impossible Turn† and his point won't be "I'm fucking amazing" or "You should go do this and get yourself killed" but "Here's what I did wrong. Learn from my mistake don't make your own".
†Despite its name the Impossible Turn isn't actually impossible, it's just probably a bad idea and you almost certainly already did at least two things wrong if you're attempting it. It's an attempt to return to your takeoff runway by doing a 180° turn after engine failure in climb out. It probably won't work because you will consume too much of your residual energy. But sometimes people get lucky.