How often to writers never respond back

after initial contact?

Noobie editor here and not sure how contacts really play out.

I received my first contact, gave the author choices on submitting the story and never heard from them again, is this common?

Yes. Writers plaintively beg for an editor here and sometimes don't follow up on offers. Almost no one edits GM, though, and sometimes someone has come here having the experience of not being able to find an editor for their GM story. When I'm not otherwise busy writing myself (I'm here to write rather than edit, although I'm a trained book editor), I offer to edit their story for them. Two-thirds of them don't carry through.

Yes.. similar experience. A lot just never respond. Sometime people contact/PM directly and also never reply after they initiated contact. But, well - it's worth it for those writers that appreciate it and you get a nice thank you, notification when they get it published and it's all good.