Let's start with the positive/useful things about this job.
As someone who had never taught before, this was a valuable experience. The initial training was really good (although you learn a lot more as you actually teach, obviously). The syllabus and lesson plans are provided, so you don't have to stress too much about that. The lesson plans are quite rigid which is a good thing if you're new, but there's always room for your own creativity. Your co-teachers will generally be very supportive and patient as long as you listen to them and make the effort to improve. After a year or more, you'll feel really confident in teaching and would have gained valuable skills and experience which would allow you to qualify for higher-paying EFL jobs.
Now for the main irritations of working here.
Follow-up Training and Random Branch Training:
Quarterly trainings over the first year took place during my teaching hours, so I had to make up those lessons by doing double lessons or find a substitute which wasn't always possible. I ended up teaching for 9 hours solid because of that! Some of those trainings could have been replaced with a powerpoint presentation or video demonstration anyway- far cheaper and convenient.
Disappearing Colleagues and the $20000 Fine:
Some people find they don't like the job and want to leave within the first year. Although there is a 1 month notice period so Hess can find a replacement, these people leave suddenly. Why? Because there's a NT20 000 fine for leaving during your first year. If you leave suddenly, no one can trace you. Therefore they leave without notice, and you have to take your share of their hours. Some of us ended up with 36 teaching hours a week for several months!
You have to do quite a bit of clerical work like filling in your own time-sheets every month (wtf, can't they just use our updated schedules to see out how many hours we worked?). If you don't fill them out you won't get paid.
Materials for Crafts:
For kindergarten or holiday lessons, you need to order the materials for the arts and crafts. Even though you ask for it a week in advance, you only get the materials right before the lesson. How am I supposed to test/demo the craft in time? I got so fed up that I began buying the materials myself (they weren't expensive) and prepared at home during the weekend.
You will get paid by the hour without any paid leave whatsoever. If you can't teach for any reason, you won't get paid. Even if your class gets cancelled because of Chinese New Year/ natural disasters/you get hit by a car. That's stated in your contract, but it's annoying nonetheless.
At the end of each month, you have to provide a report on the learning situation of your classes including your goals, objectives, concerns and ideas for improving those concerns. This just adds to the already heavy workload and responsibility.
Overall I enjoyed my experience here. The pay and support is great for a first timer. Co-workers are generally very supportive, some students will remain in your heart forever and the Taiwanese people are really kind and friendly. You can make good friends here. But learn to take criticism (you WILL be criticized, even in class! It took me a while to get used to that). You will have good and bad days just like with any job.