Too often, doing social media can become a pain. This is especially true for startup environments, run by busy people with more “important” things to do than post on Twitter and check on Facebook engagement levels.
You can define conversion any way you choose.
Marketers, especially those with longer sales cycles, often elect to call an email opt-in a conversion. It’s not wrong to do so; but let’s face it, most of your email subscribers don’t give you a lot of their time, and only a few give you their money.