The biggest reason I don't bike commute more often? Because then I can't run after work.

I run by my office, but not close enough by that I want to bike back to the office to pick stuff up after a run. If I bike to work, and want to stop and run on the way home, I have to either leave all of my belongings unattended with my bike, or run with a pack full of all of my valuables.

Or I ride home from work, get in the car, and drive back to the trails that are close to the office, which is just a waste. (And my neighborhood isn't safe to run in alone, so that isn't an option)