Umm, to tighten a QR when riding:

1.) look down
2.) make quick kick with foot
3.) miss QR
4.) hit spokes instead
5.) fall over with bike
6.) curse stupidity
7.) discover wheel is taco'ed
8.) curse more loudly
9.) bum ride home from friendly farmer with pick-up truck
10.) drive to bike shop and purchase new wheel

Now- don't ask how I know all this, please!

annie