The first step is completely different from anything else you've ever done
"Pick an instance to sign up for"
This does not compute. What is an instance? Why do I have to pick? Which one should I pick? Compared to
"Create an account at reddit.com" makes sense and is something everyone has done before.
It doesn't matter how simple the answers to those questions are, the fact that the very first step requires multiple explanations is huge, and will always be a barrier to entry.