Your boss expects you to weld with good quality but they don't expect you to answer every question there is, without any mistakes. The problem with LLMs is that they are trained purely on text found on the internet but they have no "life experience" and thus there world model is very different from ours. There are overlaps (that's why they can produce any coherent output at all) but there are situations that make perfect sense in its world model, that's complete bogus in the real world.

It's a bit like the shadows in Platons cave allegory. LLMs are practically trained only on the shadows and so the output is completely based on that shadow world. LLMs can describe pain (because it was in the training data) but it was never smacked in the face.