One observation is that I'm never late to things except when I drive. Somehow, having a car makes me assume I have way more time to get places than I usually do. When I bike, I move slowly, plan for extra time, and arrive relaxed and endorphined. On the other hand, when I drive, I'm running out the door at the last minute, delayed by traffic, totally on edge, and frazzled by the time I get to my destination. Definitely not a sustainable lifestyle for my health and sanity!
*"need" is always subjective. Sometimes I just can't figure out how to get my kids to school and to work in time without using three different people's help and leaving the house at 5am. I'm sure there's a way however, that extra hour of sleep often sounds way better.