The first steel mill I worked for, the test requirements were more of a suggestion than a rigid specification. I, a trained and skilled engineer with the capacity to make informed decisions, had to run all rejections by my boss who would tell me "it's close enough" even if it wasn't. Sometimes it bit us in the ass with warranty failures, but the warranties were probably cheaper than internal rejections (and what is brand perception worth?).

My second steel mill job, I was the one making the rejection decisions. I did the hard thing and rejected our failures but I also troubleshot them to prevent recurrence, making our product and capability better over time.

It very much matters who you buy your steel from; two mills can have vastly different performance for the same products based on how they handle these situations.