This is such an important topic. What I do when learning something new is create a Word or vim file to document my own learning process, filling in the gaps left by the tutorial as I go. That document becomes my own personal tutorial.

People who write tutorials will counter: "You can't teach EVERYTHING -- you have to assume some knowledge!" Which is true, which any parent who has endured an infinite chain of "why" questions from a child can attest. But most online tutorials could be MUCH better than they are.

I've come to the conclusion that the reason most tutorials are so bad is because -- unlike myself -- most people who write tutorials don't like teaching. They think it is a distraction which takes them away from their "real" work. But I would challenge those who write tutorials: Create a work of art! Good documentation is something to be proud of.