Barrier to entry

Why oh why do a lot of open source projects make it so tough to contribute. They get the config tools, tutorials and knowledge all sync'd up with the way they want to develop the project and then they change it up.

I wish some of them would just stick to something or find a way to decrease the barrier to entry. So more developers can contribute without spending the majority of the time just trying to compile the project.

I know this is a rant, but I had to get it out of my head.