By most measures, my bike riding is slow. If I use the Google maps "bike" feature to figure out a new route, I have to double my expected ride time. If another bike rider comes up beside me, it's a given that they will pass me.
A good part of this is the fact that I routinely ride a 125lb bike with an additional 300+ lbs of people and gear, including myself. But another part of why I'm slow goes way back to my philosophy of a bike as a labor reducing tool.
An eon ago, before I had kids and when I didn't have a working car, I decided to start riding my bike to work. I didn't know how to shift gears (or even if there were any gears - I think it may have been a 3 speed), there were hills that dumbfounded me, and my job was a physical one - I couldn't afford to wear myself out on my commute. So I pedaled slowly. Very slowly. And sometimes I would grumble "why do I even bother? I should just leave the stupid bike at home and walk!"
And then I would look down as I pedaled. And I noticed that the ground was going by at a jogging pace, even though I was putting out a slow strolls' worth of energy. And sometimes gravity would help me along, and I could go at a sprinting pace - or even faster - without tiring myself out. It was a way to move myself along with less effort. Granted, it was more effort than riding in a car, but car riding wasn't an available option unless I got a ride from a coworker. The only other option was to walk, and riding took less effort.
I think about that now when I see someone push a stroller. The box bike is something like a huge stroller, but I get to ride along too! It's so much easier to pedal than to walk and push. And considering the weight I'm moving, it's impressive how efficient the gears are at translating pedal motion into forward movement. I'm not in a rush, I'm not going to beat any speed records, but it's less work for me to move the load this way.
So the next time a Lance Armstrong wannabee buzzes past me on the bike path, I'll smile to myself, because speed isn't my focus.
It's laziness. :)