For me it's always a combination of the following: (1) not feeling ready (2) not feeling like I have spent enough time building an audience/followers around it (3) worried launch will not go as expected. What do you find the hardest?
Inbox Shield gives you full control of who is allowed to email you.
When someone emails you for the first time, you can decide if you want to keep receiving their messages, roll them up into a digest, or block them completely!