[cnr]

They are counting "one hit per IP address per day" on distribution subpages. Here is explained "DistroWatch Page Hit Ranking": https://distrowatch.com/dwres.php?resource=popularity

[angry-hacker]

Therefor it depends how well specific distro page of theirs rank in Google? If linux mint ranks 5th and Ubuntu 30th, because ubuntu is so popular, of course it gets more hits. And maybe some little known distro ranks 1st because it has no competition.

I think their popularity table is flawed, but I still love their website. You can browse distros that are based on specific distros etc.