According to Neil Gaiman, you need 2 of the following 3 things if you are to be hired regularly as a freewlancer:
1. Be a pleasure to work with
2. Produce good work
3. Always deliver on time
“People keep working, in a freelance world, and more and more of today’s world is freelance, because their work is good, and because they are easy to get along with, and because they deliver the work on time. And you don’t even need all three. Two out of three is fine. People will tolerate how unpleasant you are if your work is good and you deliver it on time. They’ll forgive the lateness of the work if it’s good, and if they like you. And you don’t have to be as good as the others if you’re on time and it’s always a pleasure to hear from you.”
Which in a diagram looks something like this:
Of course, doing all three makes you a star performer. But make sure you nail at least two and you’ll keep working at least.
ps I highly advise you watch the speech Mr Gaiman gives – it’s excellent.