It took about 5 minutes to get past the (Google) captcha.
First I clicked that I'm not a robot, but then it gave me the photos of doom. After clicking all the right pictures of a bus, say, then I had to wait while they fade out and fade in new ones rather slowly. There were about 5 rounds of selecting. Then it would pick another noun and ask for that. After a few nouns of a number of rounds each, it cycled back to the first noun. A doubly-nested loop of time-delayed captchas!
Thankfully it wasn't important.
But it makes me appreciate how someone getting locked out of their own Gmail or Google Docs must feel.
Needed to do your job today? Tough luck, better luck tomorrow maybe.
I suspect that if you have a machine that is less likely to be fingerprinted uniquely, you have to solve more captcha. In this case, I happened to be using Firefox on Linux with a few privacy related addons running. If they believe you are a bot, because you're not watching their ads, or because you are running a privacy enhanced environment, I suspect their algorithms will slow you down.
It would be interesting to prove this hypothesis. I wonder if you browse with Windows + Chrome + No Ad Blockers, if you get right through the captchas vs. if you use Linux + Firefox + Ad block or maybe even the Tor browser.