Why weren't pre-baked shadows used more last gen?

[DeadlyNinja]

We're actually seeing it a little more this generation, but why wasn't it used heavily last generation? I mean, I can understand if the game had a day/night cycle or destructive environments, but most games don't. By pre-baked shadows, I mean things actually casting a shadow (pre-baked of course) rather than dark alleys. Are they more complex than what I'm thinking?

 

[AlNom]

Memory.

 

[DeadlyNinja]

That's it? Thanks for the quick and to the point answer!

 

[AlNom]

It's a big contributor. The other thing is the amount of time needed to calculate and compile the maps. The big time waster is getting a bad result (things were only viewable after everything was done), and then having to redo it all from scratch.

Bungie made some comments about such in at least one of their weekly updates regarding Halo 2.

Fable had a lot of baked shadows and shadowmapping for their day/night cycles, and the lack of a streaming engine shows the limits of memory as there were frequent loading screens between small areas.