Lesson #1: Most roleplays dies
I have been on iwaku for five years, I have roleplayed 138 roleplays so far, only 1 have been completed. Either people get bored, forgets, aren't as excited as they thought they would be about the rp or they get busy RL and has to leave. In the beginning it was the first few things that always happened to me, people got bored or stopped being interested in the story or the characters, then the longer I roleplayed and the pickier I became with choosing my partners, I ended up getting mainly interested partners that were willing to stick around for a long time, but real life eventually got in the way and they had to drop it.
This is something that will happen to most of your roleplays, because staying with a story for months or years can be incredibly hard for some people, if not most, especially if their real life circumstances changes drastically or they thought the story was for them but then realizes it wasn't as good as they'd imagined it to be or it slowly becomes less and less exciting with time. It is hard to know exactly what you will like before you start it and many things can make or break a roleplay for a person without them realizing it.
Advice: Always be prepared for failure but have fun for as long as it lasts.