Software development with more than one person is inherently a distributed system. People work on outdated versions and in parallel and conflicts arise. Development requires branching and merging.

It is probably impossible to package this complexity into an easy UI. I like git, because it has a simple core model, but the UI could certainly be easier. Mercurials model is not so simple (e.g. multiple types of branches and commits), but the UI is easier. Subversions UI is even easier, but the model is so simple that some things are impossible (the distributed stuff).

(can we assume on HN that people have understood "simple != easy"?)