^^^^I have always shut my Mac and all peripherals, except the router, down at night and turn it on in the morning. This has been my modus operandi since 1986:
https://www.lifewire.com/shut-computer-down-or-not-4135231
Lou
That really is the best compromise if you use the computer several times a day.
I always explain it this way. An electrical device is rated for a given number of hours.
The more time it spends with electricity flowing through it, the faster you will reach that number of hours.
Electronic devices also experience stress when they go from total rest to a surge of power as you turn them on. That high stress is greatest as the power surges into the computer from the power supply and gradually decreases as everything stabilized into normal operating mode.
The more frequently you stress the components, the faster you will end its life.
So you have a choice on how you want to kill it.
You can either burn through its number of total hours of life as fast as possible.
Or you can stress it frequently until it eventually dies.
Realistically, most components are going to die at their rated number of hours (not exactly to the minute - just somewhere in the ballpark) before they will die from stress.
This experience is based on over 30 years of dealing with thousands of machines (multiple thousands).
The exception to that general trend, is the spinning hard drive. The hard drive (if a spinner) is the weak link. It is a combination of electrical components with mechanical machinery and moving parts. It will almost never reach its electrical rated life span. And will generally provide 3 to 5 years of reliable use before its days are on borrowed time.
It is also the most fragile device in the system. And it does absolutely weaken every time it starts and stops receiving power. It gets that surge of power, then the motor starts rotating those (comparatively) heavy platters. The arms have to go from a locked position of rest and start moving (like when you first stand in the morning).
The hard drive absolutely will die faster the more you turn it on and off. And it has a relatively short number of hours it’ll live comparatively.
So again, like a light bulb, you have a choice which way you want to kill it.
Hard drives also provide an illusion of working much longer because often they will “work” beyond their reliable life if they are never powered down. Only to suddenly “fail” when you eventually turn them off. The reality is that at that point, they’ve had problems for years, that just didn’t manefest. The parts have been bad for a long time. Momentum just kept it spinning. So if your data is critical, then plan to schedule a replacement cycle of 3 to 5 years on a spinning hard drive. And of course keep backups of your data.
In the end, all you can really do, is try not to use up its rated number of hours any faster than you have to, without shocking it with stress any more frequently than necessary.
That is the compromise you need to find.
If you use your computer one time or a couple times per day, turn it off when it’s not being used.
If you use it several times a day, let it run until the last time you use it that day. Then turn it off.
If more than a day is going to pass before it’s used again. Turn it off.
The dirty little secret, is that the hard drive is already going to be partially stressed several times a day anyway. When it’s not actively in use, most modern operating systems will stop the moving parts, which will then have to spin up again anyway. So you’re really only saving the wear on the non mechanical parts by leaving it on.
So you’re going to kill it no matter what. But you can postpone it’s death longer if you balance the two poisons as best you can.