[bombcar]

Failsafe design is actually really fun when you start looking at all the scenarios and such.

But one key component is that IF a failsafe is triggered, it needs to be investigated as if it killed someone; because it should NEVER have triggered.

Without that part of the cycle, eventually the failsafe is removed or bypassed or otherwise ineffective, and the next incident will get you.

[WalterBright]

Most airplane crashes are due to multiple failures. The accidents are investigated, and each failure is addressed and fixed.

The result is incredible safety.

[bombcar]

People know about that; what they forget about is that any failure is noted and repaired (or deemed serviceable until repair).

Airplane reliability is from lots of failure analysis and work but also comprehensive maintenance plans and procedures.