The steps to take to place an order are:
1) Add the items to the cart.
2) View cart.
4) At this point there are two different choices. You can use Paypal to checkout or you can checkout with your credit card info.
5) After this you will be taken to a confirm page where you submit the order.
6) This will take you to either a checkout_success or checkout_failure page.
At step 4, if you are checking out with credit card, you will need to create a login at that point. If you are checking out with Paypal, you will need to create a login at step 5. Verifying the email allows the user to access their order history. If the user does not wish to access the order history, they will not need to verify their email.
I hope this clarifies things.