With the JWST project, my irritation is in the opposite direction: how - given the complexity of the mission, with so many people involved - could so many things on so many levels go so right?
Development for it started in 1996 and it was expected to launch ready by 2007, only for it to be delayed 3 times until it launched in 2021. During that time $10 billion was spent on it, and an estimated 10,000 people worked on it. With all that time and resources it’s not really a surprise to me that everything worked as well as it did.
I don’t like to think of it as a miracle or luck (although luck obviously plays a role, it always does) per se because that takes away from the long term planning, effective management, and extremely good design and engineering decisions that made it all possible to begin with. In the end though if the people who worked on it weren’t fully invested in the process, and didn’t believe in the purpose JWST serves then it probably would’ve failed no matter how much time and money would’ve been dedicated to it.
I wish my answer was a bit more technical and not so vague in general but I don’t have any skin in the game, so this is just my opinion and not exactly a qualified one at that.
It helps that it is not particularly ground breaking (there was Hubble) nor particularly logistically complex (there's a helicopter on Mars) and there's a large pile of money ($10 billion or so) and that the people working on it tend to be sharp ("rocket scientists").
None of which is to say it is not an impressive endeavor. Just that it is incremental and built on top of a lot of engineering failures.
- They have managed to create many very sophisticated mechanisms, and run, and still running large command, to support all these mechanisms.
Sure, there exists part of technology, to design these mechanisms and to build them, but they all are impossible now, without large and very good organized human forces.
We’re basically making something to look at God.