It may be a very inappropriate example.
But The Matrix Online suffered immensely from both problems.

Basically, there were three human player organizations, Zion, Machines, and Merovingian, and you only got to play inside the Matrix.
Important things like where their respective real world bases were, weren't included in the exposition, but then some character in some quest or live event dropped some "as you know" line about how something worked, and, well, it was lame.

It remained a rather obscure game and all that's left of it in terms of documentation, are various collections of fansite material, and I don't remember it quite well myself.
So I'm not gonna beat this for any longer, but it was just something that came to mind.

Can't think of any movies right now...