system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:Why can we use WINRAR for free even though it constantly requests us to purchase a license?
gpt
It's called "nagware" and this particular approach is used by someone that doesn't want to force users to pay for the software, but they *really* hope that they will.

So they make the program "nag" the user over and over and over in the hopes that they will get so annoyed with the nagging that they'll fork over the cash, even if they'd originally planned not to.