Quiet introverts in an open plan office can work reasonably well but drop one extrovert into the mix and watch the stress levels rise and productivity plummet.
I think that's what most people don't understand. Actually, I'm not sure if it's introverts vs. extroverts necessarily, but there are definitely some people who thrive in a busy, loud environment but many people who don't, such as my (admittedly introverted) self.
My boss was incredulous when I told him that his shiny new office environment that packed 30+ people into a 30x24 ft. space was the worst environment I'd ever worked in. He told me that they'd done this because people had complained that the office was too quiet. <sigh>.
