When a single step, like entering an email address into a collection field or selecting a checkbox, is taken to subscribe to an email marketing list. This practice is considered dangerous for a sender because nothing is preventing typos or forged email addresses from being added to your subscriber lists. With a single opt-in, there could be risks to your email delivery and reputation due to both a high number of bounced addresses and from blacklistings due to high spam traps.
One of the reasons I signed up with WA is because I was having problems filling out the info on Aweber. I couldn't figure out where my affiliate link was supposed to go. I still don't know. I've listened to YouTube tutorials then when I try to do what they say I get confused or have questions and there is no one to ask. One day I'll see the live chat button the next day it's gone. I know it's me but it is so frustrating.