the thing with teaching is that we all have experience of it done well or badly (as pupils or parents, even as teachers). So those that have a view can carry on as they see fit with their comments.
To a certain extent you're right. However, if you have never taught, you cannot understand the time constraints and pressures that a teacher is under.
I came to teaching relatively late, at the age of 34.
I've done a variety of other jobs over the years....barman, computer games testing, joinery/kitchens, scuba diving instructor, furniture sales, admin, database manager.
All of these jobs had their ups and owns, but only in teaching am I working at 100% from the moment I arrive in school until I leave
I work smart, and try to be as efficient as I can, but whilst you are in the classroom you attention needs to be on the pupils (especially as a DT teacher!) So when you are not teaching you have marking, meetings, admin, pastoral duties, and the occasional break for a cup of tea - though normally this is disturbed by a colleague asking about one of your tutees, or a pupil coming to ask a question or hand in work. School may finish at 3.40, but I rarely leave before 5.30/6 pm, and then I normally have at least an hour or two's work to do at home.
But....... I love my job. It's different everyday - kids surprise and astound you (and annoy you). I learn or discover new things all the time, and I work with a nice bunch of intelligent and interesting people. And I get nice long holidays