When I was much, much younger I used to get annoyed with impatient drivers behind me. People who lean on the horn, when they think you should move more quickly. I would think 'fine, you think I'm slow now, wait until you see how slow I can be'.
Then I had an experience that made me look at it in a different light. My mom was in the hospital, I was about an hour or so from home. We got news that she was to be taken in for life saving but also life threatening surgery, as soon as they could get her in. Now when I see a very impatient driver, I remember how I felt that day trying to get to the hospital to see my mom and I just get out of their way.
I know that many of them are just being impatient for stupid reasons, but I don't want to be the spiteful asshole purposely delaying someone, who may have a very good reason for being anxious to get where they're going.