I've seen this delay in action when logging in into an old dormant Google account. After I provided correct password (and some other details I remember vaguely - probably no phone number set and some problem with using the TOTP I set up long ago), it sent an email to the linked primary email and waited for a day to give it a chance to abort before logging me in.
The delay is quite a bother but it's surely better than account takeover. What I mind about the process is probably the lack of transparency - what combination of factors (MFA pieces, location, inactive time, ...) launches which process? I get that transparency might help attackers here but they're the ones to have the persistence to figure out the rules anyway. Smells like security through obscurity to me.
The delay is quite a bother but it's surely better than account takeover. What I mind about the process is probably the lack of transparency - what combination of factors (MFA pieces, location, inactive time, ...) launches which process? I get that transparency might help attackers here but they're the ones to have the persistence to figure out the rules anyway. Smells like security through obscurity to me.