He built from what others threw away.

The troubleshooting did not begin in an engineering classroom. It began at a racetrack without much money. If something broke, a new part often was not an option. Other racers threw damaged pieces away. He picked them up.

Every failure taught him something. He learned to ask what actually failed, why it failed, what was still usable, and whether two broken pieces could become one that held. That is still the method: understand, diagnose, solve, implement, verify, improve.

Later the equipment changed — construction, Halliburton, DY Concrete Pumps, Boeing. The question did not. What is actually causing the problem? That is the man you hire.