Depends on the individual to be honest.

I wouldn't stick with one thing until you achieved perfection.... because for one thing you will never achieve 'perfection'. And because you'll never try the other aspects of 3D. I would recommend following a few tutorials... try some modeling, some rigging, some animation, some lighting and rendering, some effects, and what not... Play with whatever you can get your hands on. You'll soon know what aspect of 3D is for you.... then you try to achieve perfection.

Have fun