This is one of the more decent advice i read online.
Yes, its easier to crticize someone's work and yes we are wntitled to a certain level of service for our payments say in case of a phone company or a food chain but like you explained, people should be more aware of the human factor that people at the counters and call centres and other workers arw humans and they have problems and limitations too. They could be having a bad day for all you now. So breathe 5 times before you start berating a security guard or a doorman or anyone. Watch your anger.
And the idea that you can his/her job better is only a fragmentation of your mind. Dont let it fool you. (:
Thank you for the piece.