I'm not sure how much more mystery one neds than 'Only orbiting telescope in human history has a fault our best engineers haven't diagnosed as yet!' :-)
> A NASA history of the Hubble,[24] in discussing the reasons for switching from a 3-meter main mirror to a 2.4-meter design, states: "In addition, changing to a 2.4-meter mirror would lessen fabrication costs by using manufacturing technologies developed for military spy satellites."
Hubble was derived from these spy satellites.
There are estimated to have been something like seventeen of the KH-11 satellites, each one of which cost something like 2/3s of a Nimitz class aircraft carrier.
https://en.wikipedia.org/wiki/KH-11_Kennen
And there are an unknown number of its successor, but probably at least 3, where they updated it for stealth.
https://en.wikipedia.org/wiki/Misty_(satellite)
It feels like a parallel universe where what is a technical struggle and tour de force here, is churned out by the dozens.