Coffee Space 
I’ve done a little teaching now, and I have some fun observations I’ve made over time. These probably ring true for many other people too, and some may disagree with them, but these are just the observations I’ve made.
You cannot mentally checkout in front of a class as you may do tucked away in an office. Sometimes people mentally checkout at the end of a day as they become tired, slow down their pace of work, etc. You are not afforded this luxury in teaching. If you’re teaching for the entire day (which you’re expected to do), you have to be alert for that entire time.
Teaching is mentally and physically exhausting. Talking for hours and hours straight is not something most people do. You’re also standing for that entire time, walking around, gesturing. Try teaching for four hours straight and let me know how you get on.
As a teacher, lunch breaks are just opportunities for you to catch-up on mandatory emails and communications that people love to send. Many times now I have not been able to eat much lunch, because there is simply too much work to do.
When teaching, you are expected to be on call at all times. It’s not rare to get a call on Friday night informing you of work that needs to be done before Monday morning. This is just expected of you. You don’t dare may plans that may use the entire weekend, because at any time someone could offload a pile of critical work onto you.
You are expected to work outside of work hours. You will not be compensated for this time either, not at normal rates and certainly not at overtime rates either. The concept apparently simply does not exist. You begin to understand why people refuse to answer any communications whilst outside of office, but then these same people can also expect to have their concerns dealt without out of office.
Some people hold onto critical information for long periods of time without sharing it. This means that the people that needed that information get it with a large delay and have to work out of hours (unpaid) and are unable to prepare for the incoming additional workload.
Students are very happy to send you large documents just before a meeting, and then ask you whether you have read it and processed it. Teachers may seem to be like infinitely capable processing machines, but it takes even them time to figure things out, especially if the language used requires additional processing to even read it.
It doesn’t matter how many times you explain the same thing, students will keep asking the same questions and making the same mistakes. Some, maybe even most, will understand and absorb your message, so it is worth telling. But those that do not, it doesn’t seem to matter what you say, you will make no progress with them. They will run into an issue, and then ask you about the thing you have already repeatedly explained.
Students will ask you to explain something, and then immediately checkout, so that none of it goes in. It’s an expression where you can see they have gone somewhere else, and you feel this sudden burden that you are not talking to a human any more, but somebody running entirely on autopilot. As a teacher you already have to do enough thinking, without having to also do the thinking for other students too.
During teaching sessions, a significant number of students checkout. I know this, because I get asked to clarify the points quite clearly made by other teachers. It’s important than when designing teaching sessions, there is some process of recaps and reiteration - not just in the session, but other sessions too.
Students are mostly happy to do the absolute minimum to pass, and do not enquire or explore outside of the scope you provide them. It’s incredibly frustrating to see students work through exercises by simply copying what they see, and not thinking about what actions they are doing critically at all. A few students will ask “what is this doing”, and the far fewer better students will even experiment with the exercise and ask “what if”.
Good students are hard to keep engaged. This is something that appears to be difficult to address in general. My current solution is to invent challenges for students to expand their knowledge, but this can take away time from students that need help too. There doesn’t appear to be a nice answer here.
Students will not turn up to many sessions, and then magically expect you to help them catch-up. Students can literally not turn up and then have some expectation that you can help them catch-up in just a single week.
As a teacher, coming up with scenarios on the fly is hard. You want it to obviously be conceptually clear, but also interesting. You find yourself reaching for similar scenarios each time, but that ends up somewhat boring. You can reach for a new scenario, but then this carries risk of being conceptually problematic.
Live demonstrations are difficult. Just pick typing for example in front of a class. You are usually doing this whilst standing, in front of an unfamiliar computer, on an unfamiliar keyboard. On top of this you have the pressure of being watched, it’s not an easy environment.
Staff do not get paid enough to teach. In the UK you have full-time experts earning about £50k a year (from what I can tell, because nobody wants to speak about pay in the UK), with very little benefits. Once you take off tax, living costs, etc, there is really very little disposable income. I would go far enough to say that there is not enough disposable income for a single person to hold down a mortgage.
Overtime does not exist. If the work takes you longer that the allocated time to perform it in, that’s on you. Your pay will not increase to reflect this.
You are not paid to do workplace administration. All pay is allocated in terms of teaching, so there is nothing allocated to perform important administration. Occasionally you get an important email “you must fill out this form now”, but there is no time allocated for this.
A friend and I reflected the other day about how we don’t believe we match the standards of our teaching peers. It’s likely that we’re holding ourselves to the high standard of people working in the field for a long time, but also it could be somewhat true. Teachers do not pay as well as industry may, so if you’re a good teacher, you may be dragged into the industry anyway, because the pay is better.
Do I recommend teaching? I am yet to decide. It is obviously not without challenges and difficulties.