How much does volume matter when breaking in amps and cables?

I think it is also a myth that people buy expensive gear that they don’t like because they’re told they Will like it later. 

I think some fail to return equipment they don’t like, hoping for the glorious moment that mesmerizing sound takes over their rooms. By the time they figure it’s not going to happen, the return period has passed

jL35, people do not buy expensive gear that they do not like. They buy expensive gear that is flashy only to find out that they do not like it then are told "Gee, you just have to break it in." People like geoffkait are suckered into believing that is true. 
Aberyclark, try not to buy equipment you do not like which admittedly is not easy. I cower to think how much money I have wasted over the years. It is always buyer be ware unless you are geoffkait then everything you buy is just wonderful especially after it breaks in. The only item that breaks in is your brain. Of course certain people, who shall go unmentioned have a hard time finding theirs. OK moderator, is that polite enough?

@mijostin  
millercarbon there is a huge difference between mechanical devices and electronic devices. Undoubtedly, electronic equipment drifts slowly overtime as some component values shift with recurrent heat cycles although I have never seen objective evidence of this. There is no electronic device that I know of that changes its characteristics in the first several hours of usage. Imagine what that would do to computers! Certainly tubes need to warm up and stabilize. Maybe class A or highly biased AB amps sound a little different after they heat up although having had several class A amps I have never been able to hear this and again have not seen any objective evidence of this. People come up with a bunch of fuzzy theories why electronics and wires need to break in. All of them conjecture, mythology. I can say that all the full range ESLs I have dealt with do require a period of loosening up. Their diaphragms are tightened up with a heat gun after they are mounted and they do relax over time. This only effects the very low end. Perhaps some dynamic woofers may improve with break in as you can imagine their spiders and surround loosening up a bit with use. But again I have never seen any objective evidence of this.

Thanks for the above. I make tube amps. I cycle and burn them in for 24 hours but only to catch the infant mortalities, which I do. If burnin of electronics was real why wasnt it "discovered" in the 1950's?