not a huge sum, but I had $10k in it, because it was a fun bullshit app that scratched the lottery itch despite it earning less than regular interest over my time with it

adding on to this, the bank isn’t doing just mfa, it’s likely also doing risk-based authentication. logging in and viewing funds isn’t that risky, but moving money around is much riskier, even in the same account. so you have to provide stronger evidence that it’s you requesting the action.