Do I NEVER shut it off…?

this is my response in these power on threads.  
i have a couple amplifiers that are over 30 years old.  i always power down when not in use.  they still sound great today, even after a short warmup.  
i do this with my newer amps and preamps too.  
would my 30 year old amps sound this good today if they had been powered on continuously for the past 30 years? 
dont know, dont need to.