the key, is that it limits the amount of information you need from the user to create a relationship with them. getting an email address and password is the ba

the key, is that it limits the amount of information you need from the user to create a relationship with them. getting an email address and password is the bare min you need to communicate with them. in some cases, i have only requested an email address and then sent the password in the mail. this solves a number of problems and if the user just uses the password, then you can assure they have a somewhat secure one.