free space on ssd

My skill testing question is: why is it that in Explorer, I'll see the free space on my SSD down, let's say, about 30 Gigs. After a nice fresh reboot, that space is freed up.
It seems this is is not a continual thing but once in a bit, I'll notice the free space isn't what it was then as said, a reboot will rectify that. Any ideas as to why that is?
If any are not sure, just make something up because I'll believe just about anything. Thanks.

Tried doing that but no difference. I've dropped about 12 gigs since rebooting several hours ago. Any further suggestions?

Would there be that many log files being created within a few minutes?

Haven't taken ownership of nothing. But I'm having problems finding log files. I'm in Explorer and on the C: Drive Search, I type in logs and all I'm finding here is something dated back to 2016. When I double click on that, I only get "Element not found" ... so I'm totally stumped even as how to find the logs. Let me know what you think.

I've run that wee program and it just keeps going and going and listing logs (I think) so this is becoming waaaaaay too complicated.

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Maybe someone else has an easier solution for this exciting perplexity ...