Human-centered design requires us to observe human behavior with beginner's eyes, so that we can spot the innate ways people interact with the world around them. We call these intuitive and unconscious reactions Thoughtless Acts, and IDEO designers collect photos of them to inspire their work.
I took this picture at the train station right next to our Palo Alto office. At first glance, I thought it was an unusual fashion statement, but then I realized that the woman in the picture solved a common problem in an elegant way: When your bike lacks a chain guard, your pants can easily get stuck and you risk destroying them—or even causing an accident. By wearing a cut-off sock above her pants she kept them protected from the chain. By going with a chartreuse sock, she made sure she wouldn't be overlooked in the aggressive Bay Area traffic.
Unfortunately, I discovered this helpful little hack the day after I ruined my favorite yellow pants with chain oil. But don't pity me too much; in the end my dry cleaner saved my day, and from now on, I'll always carry a cut-off sock with me.