The theory behind sportbike design has always been to make a perfectly aerodynamic machine that is designed for racing and able to pierce through the air with minimal resistance. From the front fairing to the rear tail section everything has been carefully cut to slice though the wind more efficiently.
In order to make bikes legal for use on the street, manufacturers have been forced to install two large mirrors that not only can disturb airflow but also break up the clean and sleek appearance. Quite often, stock mirrors do little more than offer a fuzzy and buzzy view of your shoulder as they're kept as close to the upper fairing as DOT regulations will allow.
A quick fix is to simply remove the mirrors and add block-off plates, but not only is a bike without mirrors an easy target for a quick ticket, but you can't see the sneaky bastards pulling up behind you, either. Adding a set of aftermarket mirrors can keep the cops off your ass while providing a quick glimpse of the bikes smelling your fumes behind you.