What's the Difference Between Normal and Serial Complainers?

A study by manchester mats, and this is going back to the airports. A serial complainer is someone who makes more than 50 complaints a year. And they found really interestingly, that a serial complainer would tend to send all of their emales between ten p m and one a m,. Then again in the morning, from seven a m to about eight a m. So what that suggests is that the normal complainers are actually being woken up by the planes and got off, for god's sake, and sending an email.