Why No Power Button on Some Phono Stages?


I am upgrading my phono stage, and several of the ones I have shortlisted do not have a power switch/on-off button.

Why is this? Is the user supposed to keep it powered up all the time, or manually unplug the power each time?

I know certain electronics are supposed to have better sound once they have reached thermal equilibrium, but that doesn't mean I want to keep it powered up 24/7.

Switching the phono stage power off from the power strip is a PIA, as it would switch all of my other components off, and I'd lose by tuner settings.

I want to choose the phono stage by sound quality, but an on/off switch is a major convenience factor for me. Why do some manufacturers leave it off?
kixo
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It takes substantially less play time than stand-by to worm-up. My area is vulnerable to devastating surges so my equipment is always OFF when not played. It takes one full album to play (near 40m) and wormup of Musical Fidelity XPS and pretty much the rest of system is complete. Do home errands while worm-up tunes are playing. They still sound great. I shut down my system or turn on with single button of Furman conditioner and care less about power switch on my phonostage.
At last we discovered some advantage of the tube amps:
one can turn them off.
My tube preamps are on permanently. No issues. Every now and then I turn them off for a day or 2 to discharge the power supply caps and ensure there is no behavioural memory imprinted into the power supply caps.