Users vs Customers
Something I keep seeing (paraphrasing...)
We have XXX customers using our software. They all love it and provide us great feedback. I don't think it is a good idea to charge them yet.
Two things come to mind:
First - It is never too early to charge someone. The feedback you get from someone who pays you is infinitely more useful than someone who uses it for free.
Second - You do not have customers until you get paid. Before you get paid, you simply have users. If your product solves a problem, do not be afraid to ask for money. Maybe you ask for less than you hope long term, but you certainly ask. If all of your current users refuse to pay, this is also great (although sad and sometimes hard to swallow) feedback as well.