Ah, if only the budgets were big enough to staff only engineers (but they never are). Then Designers could just focus on ‘planning’ the game.
And sadly, I’ve seen programmers introduce way worse bugs then designers. Designers are within a ‘sandbox’ and are firmly restrained. But the programmer can wreck great havok in C++. For the average AAA project I am that guy that gets pulled in to fix those buffer overruns, data race conditions, NaNs, and memory stomps (sometimes for optimization but not often). I would estimate many, many man hours are wasted away putting out fires
Granted, some of this might get alleviated if people didn’t have such strong egos in my industry and would let someone peer review their submits