Exactly - you start setting up, then discover a 100 year old shutoff valve, which then breaks off in your hand, or there's mercury in an old heating system, or

Exactly - you start setting up, then discover a 100 year old shutoff valve, which then breaks off in your hand, or there's mercury in an old heating system, or water leaks appearing 10m away from the source... In both programming and plumbing there's no substitute for years of experience in learning how to handle uncooperative reality.