Forced to unlock Apple ID at least once a day

My wife has an M1 iMac, and an iPad mini. She does not have a cell phone of any kind. Her Apple ID does not use two-factor authentication. She is forced to unlock her Apple ID on these machines routinely--generally at least once per day. To unlock, she has to go through answering security questions. I have multiple Apple devices, including an iPhone and I use two-factor authentication. If I even have to give my Apple ID password once a month for something that's a lot. I have never been asked to answer my security questions. Anyone have any ideas as to what causes this and how to fix it--or at least make it better? As for two-factor authentication, any reason not to enable it?