Space and Planetary Probes and Telescopes:

[beecee]

Some sad  from NASA this week is that the  Chandra X-Ray Observatory is dead. On Friday, Oct. 12, 2018, the space agency said that the telescope automatically went into so-called safe mode. Also the HST went into hibernation last Friday 5th due to a gyroscope failure. Yet Voyager 2 is nearing the edge of the heliosphere, which Voyager 1 has already left. Obviously everything has a "use by date" but did we make things better 40 years ago? The Mars Opportunity Rover  I suppose is an exception as is probably the Curiosity Rover. Probable reasons I would imagine is that the HST simply has more intricate parts, such as its gyroscopes and mirrors...So what other reasons facts would determine how long space probes, rovers etc last for?