Down the years we know the tried & true requirements to keep a car running smoothly. There is a lot more riding on lack of car maintenance simple user wear & tear. Taken to its extreme, car neglect can cause injury / death.
Alterative though, I am somewhat surprised that you do not seem to see what I was hinting at, regarding Hi Fi equipment
I would not criticize anyone for going through some regular regimen, cleaning their own Hi Fi plugs and connections' in the home. It is a reality that -over time - they gather " surface grunge /oxidization" on the conductive materials used in electrical cabling and plugs. Besides such a DIY cleaning procedure costs a listener.... nothing.
To me, Hi FI is about bringing together some individual choice of combination equipment that personally suits me. I require it has longevity, reliability and actually simply , does what I demand...without any form of strain either electrically or musically. After all, the Industry to remain valid- claims it is also all about "investment". The ability to sit down , use and forget the equipment, and then ....now....ENJOY the music.
As far as listening to dealers/ repairers suggest ....wanting to forever 'tinker-tinker' to improve what one already possesses....I have no patience. If something for a justifiable price apparently "better" comes along..... I will use my own non -outside and uninfluenced opinion to strongly consider new purchases for my various systems around the house.
The stories one has heard -down the years of gullible insecure Hi Fi enthusiasts 'taken in' - by opportunistic dealers/ repairers, is lengthy!!
IE A fella I knew once that had a pair of top speakers : subsequently he had been talked into allowing a clown of a dealer/repairer to 'improve' their performance. It happened to involve the complex cross-over network system being 'tinkered with'...
Alas! ...when the man got them back home, it was not long before one or two of the speakers in the Units ...were blown. Worse, several years had gone since they were 'the current model'. ...and replacement speakers were now unavailable.