Also individual contributors often fail to grasp the big picture, what seems like an insurmountable issue to them is irrelevant or not a priority in the grand scheme of things. Or it's a pain point for them - but dealing with it will hurt the project overall. Can't even count the number of development/design/product bike shedding discussions, wasted effort on covering edge cases, etc. on features/products that get scrapped once they get tested by users.

This is why I hate managing people - I hate having to deal with all the egos and trying to empathize with everyone to try to get a sense of where they are coming from just to judge what's important or not, and weighing political impact of different calls. Code is simple by comparison.