Essentially for a long time it was the worst game sold Steam...

Basically as a rick roll type of giveaway. Dude would promise skyrim or a similar AAA giveaway in the forum, and link a giveaway to a crap game, the game being bad rats or fortix. That's also the origin of "thanks for skyrim" meme comments.

Basically imagine promising baldur's gate 3 in a thread and you click the link and it leads you to a 3 dollar worth mostly negative sex game giveaway with comments saying "thanks for bg3"

For context, it's important to remember that at one point the only way you could get your game onto Steam was by having someone who worked for Valve specifically look at it and approve it.

This meant that there were few really bad games on Steam. Obviously there was a range of quality, but you didn't get shovelware like you did today. The problem is that it didn't exactly scale, so we got Steam Greenlight and later the current pay-to-play system with a few guardrails to limit a game's reach until it has a certain number of sales.

Bad Rats was one of the few comparatively bad / shovelware-ish games to slip through during the era where Valve curated everything; on top of that, while it was bad, it was at least very cheap. So it became a bit of a meme to give it away. Nowadays it isn't even unusually bad; it's easy to find way worse games on Steam. But way back when it was a bit shocking to find a game like this on Steam at all.

It even got a sequel 9 years later
https://store.steampowered.com/app/393200/Bad_Rats_Show/

I just had to 😅

No judgment here, don't worry 😂 that's a classic for a reason XD