Well "required" is not exactly right. You can accept funds manually that way if you prefer. But if you set your account up once to auto receive and deposit then any funds anyone transfers to your email address will just appear in your account. This is done once in your online banking setup and after that there is no clicking of links or logging in or passwords necessary.

Is there a reason to not configure it this way? I've always set things up this way, with the three banks I deal with, and can't think of any obvious ways I could get burned or fooled.