Our friend in Japan thought her computer was on its last legs.
Our newish notebook sized computer started up very smartly when it was brand new. It hadn't done much work but it had slowed down to an intolerable start up time. I gave it attention. I looked at all the things it was loading on start up and stopped them. I don't know how they all got there, but they did.
I stopped everything except the operating system and the virus checking from loading on 'start up' and lo and behold, it started up fast once again.
A friend of our friend in Japan gave her computer some attention and stopped many things running and cleared the 'furball' from the fan. Her computer is now working perfectly. Fingers crossed it still is.
To put it bluntly, you don't want unnecessary rubbish loading up when you start your computer. Crush, kill, destroy. You stay in control of your computer and what it does.