These types of games are rarely suited to the constrained nature of home console hardware specifications. Large, open-world, sandbox type affairs is where this kind of thing happens the most. All of these things not only impact on overall image quality but also take you firmly out of the lavish world the developers have tried so hard to create.
The framerate often tends to suffer, texture detail gets scaled back, and sometimes the framebuffer resolution takes a massive dive.
It is pretty commonplace to say that titles which feature much in the way of dense foliage, high levels of geometry and plenty of alpha-based transparency effects usually have serious issues with performance on consoles.
