I think the simple answer is given enough planning, time, resources and the right kind of leadership and precise execution that brings it all together, you can ensure that something as complex as JWST can be made as well as it did.

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.

I think that at this level of precision, the only role luck plays is in affecting the timeline and budget required to mitigate luck’s effect on the project.

I think this might answer your question. https://aerospaceamerica.aiaa.org/departments/how-nasa-decid...

Waterfall design and big ball of mud architecture.

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.

This is mostly question of very good level of organization, or if in terms of University disciplines - management and decision making.

- 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.

Not that I doubt, but it would be nice to have some handy evidence for your positive evaluation.

I think they might have people that actually care about the vision (no pun intended) of what that telescope means. That kind of alignment isn’t always possible on many endeavors.

We’re basically making something to look at God.