This is such a clever idea for a game because it takes something normally annoying — captchas — and turns it into the actual challenge. The timed sections make it surprisingly stressful, but that also makes beating your previous score feel much more satisfying.
I also like how people in the comments are comparing scores and trying to improve their runs. That kind of simple “one more try” design is what makes browser games so addictive in a good way. I spend a lot of time playing quick titles on BunaGames, and CaptchaWare has that same instant-play feeling where you understand the concept immediately but still want to keep improving.
The mix of humor, speed, and frustration works really well here. Definitely one of those games that sounds ridiculous until you actually start playing it.