To leave on ... or turn off. ..

My 3 main PC's here are on 24/7. Maybe sleep, but that's about it.

The main consideration is power consumption. With newer components, heat is not an issue unless you are really using it hard. And at idle, most PC's are less power consumption than a 100watt lightbulb.

Meet in the middle and use sleep mode - benefits of low power usage like turning it off, but ready to go with a wiggle of the mouse like leaving it on.

Generally, I leave mine on throughout the day whether I'm using it or not, and then put it into sleep mode at night when I won't be using it but if I woke up and needed quick access to it then it's pretty much ready to go instantly.

By turning your computer off it does not get windows updates nor does it get anti-virus updates.

I have had many people need viruses removed not because they had no antivirus or they had some crap one, but because their databases where 6 months old because they would shutdown the computer before it could finish updating.

Not to mention this can really slow down the computer and backlog it with updates and virus scans.

I will add my 2 cents worth, only with verified facts not opinion.
I have been in the electronics industry since 1964. During that time I have learned many facts about turn off vs leave on. I would like to share these with you. I was very impressed with your article in general and hoped to add some little known or thought of facts.
1.) Wear and tear from turning a system on and off. In 1968 I worked in a group that had complete access to the Collins Radio Corporation in Irvine California's Electronics resources and labs. While there it was clearly demonstrated what happens inside an integrated circuit when power is turned on. We watched as a glass covered IC was put under the microscope and the power was turned on and off. Each time the power came on the extremely tiny little connections that connected the outside world to the internal electronics of the IC would jump remarkably and extensively. The point was to show that repeated power removal and application will absolutely eventually cause a failure. The result was they never shutdown any mission component that needed to be available for Production. They explained it very simple and straight forward with the question how many people have seen a light bulb fail when it was turned on! 95% of the times those failures happen at that instant. We were seeing why under the microscope, it is not and calm as you would expect under the hood of an IC. This was also supported by television technicians that would see a flurry of failed television service calls always from customers that left n vacation only to come back and the TV did not work right (which I saw my share of and would always ask the customer did you just get back from vacation? the answer was always why yes we did).
2.) Hard drive bearings. Hard drive bearings get the most wear and tear not from running but during the spin up and spin down not to mention the power IC circuit that spins it up also is tasked heavily during this time. Once a Hard drive is at its optimum running speed the power consumption falls dramatically and the bearing load is almost nonexistent due to the gyroscopic nature of the spinning platters. Load on the bearings become close to nothing at that point. Any time the drive is stopped the bearings then pick up the task of holding everything still and smooth till it stops and also during the spin up the same process. This causes the maximum heat on the bearings during the life of the hard drive. We have more than once had clients turn a computer off to go on a trip or for a holiday only to find the hard drive would not spin up when they turn it back on. I have yet to see a hard drive freeze up or reduce speed while running consistently. I have in my possession a hard drive i kept that had been running for 3 years with no issue, the desktop was replaced so the old desktop was set aside. 1 day later it was discovered that they needed some additional information off the old system. We turned it on and the hard drive had failed. I was curious so I thought I would investigate what happened to this drive. I eventually had to open it since it was not spinning up I thought if we could carefully open it in a clean box we could spin it up and get it running to get the data off. After I opened the drive I found the bearings were frozen so solid I could not even turn it by using a pair of vice grip pliers on the hub. 3.) a major source of danger. I have had clients that would go on vacation and unplug their computers to avoid lightning damage, which on the surface sounds reasonable. This is fine as long as you also unplug all network or other lines going to the system that may also transfer lightning down them. If not you may have what happened to a client of ours that burned a hole in the side of their home because in trying to save the computer the lightning had no place to go so it went through the wall and started a fire and blew a cement pad clear out of the ground in the process.
In summary you may see I am an advocate of leaving the computer running. These are only the major points you clearly have shown some of the other detrimental issues with updates or remote management access, security patches not installed, systems not able to have enough idle time to due housecleaning tasks, backups not able to be made and in the case of a larger organization possible network resources taking a hit because all the employees turn their systems on at the same time and there is a sudden need for updates going out to every system all at once loading the network down. I appreciate the opportunity to add my 2 cents in.
Oh and while I am rambling people need to replace their Surge Protectors on a regular basis, they are rated in Joules (Watts/Second) so they can become deteriorated and show no signs of their inability to protect the systems after a few years. We typically recommend replacement every 2 years regardless. That was just a side note.