Bikes are remarkable efficient. If your commute is under 10 miles, and you live in a relatively flat place you can get to work on a bike about ten minutes slower than driving, and you’ve used no gas, taken up less space on the road, and can park right by your door, for free.
Well there is that issue of coming into the office drenched in sweat if the temperature is 90+ degrees with 100% humidity.
In London and many other British cities the congestion is so bad that it's a lot quicker by bike than in a car, not ten minutes slower!