I don't believe that's the case. Alerts will still be sent without logging in. It's just that the automated checks only happen with a certain frequency, daily or so. If you log in after an alert-worthy event happens but before the automated check, you'll trigger an alert e-mail because that's when it sees the event. If you're logging in a lot, it might look like they only happen when you log in.
Comments
I don't believe that's the case. Alerts will still be sent without logging in. It's just that the automated checks only happen with a certain frequency, daily or so. If you log in after an alert-worthy event happens but before the automated check, you'll trigger an alert e-mail because that's when it sees the event. If you're logging in a lot, it might look like they only happen when you log in.