My mum was a teacher for a bit. Did her training in 2008, quit at the end of the 2015-16 academic year because she wasnt enjoying it.

She was only doing part time, yet was still constantly working even when at home. If she wasn't planning lessons she was making resources/worksheets, or she was marking homework, marking tests, marking coursework.

She found the students didn't seem to appreciate teachers - she taught languages, which, in the UK at least, students typically hate and don't see the point. As a result, students don't put in the effort.
Her school was a grammar school, so predicted grade were high (set by the school).

At the end of the year, actual grades were compared with predicted, and my mum always felt like the faculty attributed good scores to the effort of the students, and "poor" scores to the effort (or the lack thereof) of the teacher, when sometimes she had to spend a lot of time and effort in getting the students those grades.

Students don't thank you either.

I really do believe teachers are underappreciated. They should be given more credit for what they do, whether by praise and/or by pay.

And yes, teachers may get decent holiday, but you can guarantee they will still be working through them, and if they go away holiday prices are more expensive than for people who can take off time at low peak times