And at the same time, most captcha solving services I've tried break recaptcha with no problem! And they aren't even expensive. Now, I dunno if they use fancy ML techniques or sweatshops with little African children receiving electroshocks when they get one wrong, but they do work to the point that nowadays captchas only repel legit users and very badly engineered spam bots, the good bots are already ahead of the game... I even thought of writing a browser extension that would use a captcha solving service to save legit users from the pain of captchas, but I'm too lazy to do it...
I think all CAPTCHA solving "services" that offer reCAPTCHA solving rely on human work, and thus work on a delay (which obviously is just a minor inconvenience for any mass spamming operation). Here's a pretty nice article about it.[1] ReCAPTCHA itself remains unbroken to date (and it sure has gotten harder over the years too).
There are some services like "Captcha Brotherhood" were you get points for solving captchas of other users, which you then can use to let other users solve your captchas.
