The goal of lowering the rolling resistance for a cycling wheel is to make the wheel easier to roll. Rolling resistance occurs at the contact patch where your tire makes contact with the road surface. The higher the rolling resistance, the harder to move the bike forward, and the more watts wasted.
The FLO 49 AS was designed with a wide internal rim width to shorten your contact patch, reduce the rolling resistance, and use the watts put into the pedals to move you forward. Be wider, be faster.