Let us see what the most common are:
There are so many verities of eye frames and there are many options for every face shape. These help to balance the look such as for some face types, certain frames can accentuate or even slim certain features. When you go out to select frames, ask sure to try out many and see what suits you best.
Some professions might request for a specific type of frames. For example, for going to beach party, one may choose some fashionable frames, but when you go back to your corporate workplace, more professional frames are needed. This also could be driven by how comfortable you feel wearing those frames.