E.g. Nurses don't really care about their patients.
Or firefighters just sit on their arses at the station most of the time so why are they whinging?
Or the police are all corrupt.
Actually, all of these opinions are bollocks. But I wouldn't dream of slagging off a profession that I have no proper understanding of, so why do so many people feel the need to slag off the hardworking teachers of this country? GRRRRRR!