I'm pretty sure it's part of "the algorithm". I don't get 2FA prompts every time, but ever so often for it to be annoying - especially since I am then thrown back to the login prompt which dares to tell me that the password from my password manager was wrong. No, it wasn't wrong, your system apparently just cannot handle going from a password prompt to 2FA and then realizing that the correct password was already entered! I asked lots of people around me and they don't have this issue, so I guess it's kinda random who is treated how.