Two reasons. Foremost is I can not find a look that I like at any bike shop or online bikes (Trek, etc). Second I need an XL frame and that is often hard to find local. I did find a bike I liked a few months ago, 2016 Trek Talon 3 gray/black with lime yellow-green, but could not get my hands on an XL anywhere. Frustrating to find an XL in a design I like. Thus build, paint it myself.