Health and efficiency.I got sick. First time in over two years. All my co-workers were sympathetic and repeatedly offered up, "well that is what you get for riding your bike in this weather!" I hated being sick, ten days of not riding. What ticked me off even more was I had not driven to work since October. Three clear months of no driving to work was a record for me.
Luckily, I got well enough to commute in the most recent giant snowtacular: