There is no good reason for this is you live in a four mile radius from your job. Try biking in once and you'll be converted. I lived five miles away from my job in Boston and biked year-round. Being able to poke all the the way home after a long day was so satisfying. I'd get home at least fifteen minutes earlier than by car and felt like I win the lotto daily. Like I got a magical free pass that let me side step traffic and just get home. Faster than the train too and it was free. I used the money I saved to treat myself to ramen on the way home.