I ran into a situation earlier this year where I tried to log in to my Google account in a pinch on someone else's computer and I could not because, even though I did NOT turn on any fancy 2fa options and had ONLY ever wanted Google to use my phone number or alternative e-mail address (at MOST) for such purpose, they refused to let me log in unless I approved some special 2fa mechanism in the YouTube app I had logged in on a Google Fi Android phone that I only use for testing and had over a thousand miles away from me at my desk. It was ridiculous.

In another, non-Google case, Apple once demanded that I provide the answers to challenge questions for an account I didn't use often even though I had my username and password correct. To me, the challenge questions are something that should only ever be used to verify in the case that I don't know my password, and it took me three days of trying against the rate limit to get enough tries to figure out the spelling of the answer for one of my questions. What made it really ridiculous is that the only reason this account existed was to give me access to developer account that was actively billing my credit card that I couldn't access... at least with Apple there was a customer service representative who was willing to try to figure something out as they agreed that it was ridiculous that I was paying money for something I couldn't even log in to cancel (though she wasn't sure if she could actually do anything...).