^ This. And more advanced design and manufacturing methods that have come as a result of the proliferation of CAD design and analysis software. Also, metallurgy

^ This. And more advanced design and manufacturing methods that have come as a result of the proliferation of CAD design and analysis software. Also, metallurgy in general has improved leaps and bounds in the past few decades. Regardless, there is a lot of ways for welding to go wrong. That's a design consideration that engineers try to drive out of the equation, especially in a situation where they're responsible for the safe usage of a multi-ton piece of machinery that can move at 100mph.