i guess if u kno abt the way a model is built you then kno how to animate it...i mean if you are working with low poly models then there is limited movement it can have and therefor in animating you would have to appreciate this. similarly if u know the way in which the model was built it can make it a lot easier to distribute the weight of joints.
My only real advice would be that if u want to be an animator do not get urself roped in to building models all too much. simply because u will create a model and not be totally satisfied with it and you will try more and more to create the image that you have in your head. eventually you will end up with something that is far too complex to animate. what i suggest is that you find someone that can model and animate their models.

but as has already been said its nice to have a little background knowledge