Although I really enjoy teaching English in Japan, there are some things that are rather demanding. In fact, it takes a certain type of person to really thrive as a teacher of English.
Patience is a virtue
Teaching English requires patience. Your job will be varied, teaching both children and adults, so if you find children test your patience then maybe TEFL isn’t right for you. On top of this, your students will make mistakes. Countless mistakes. Sometimes they might not understand what you are trying to teach them which can be frustrating. If you are a person who has patience and the desire to teach you will thrive in TEFL.
Although there is the chance to teach English in your home country, most TEFL positions take place abroad. If you consider the idea of moving abroad to be daunting, if it strikes terror into your heart to be a foreigner living away from your family and friends, then TEFL might not be for you. Setting up home in a new country takes courage and determination.
Or maybe your English isn’t up to it. TEFL demands a good command of English, and the ability to communicate clearly. Even for native speakers this can be a problem, so weigh up carefully whether you have the kind of language skills that are required in this industry.
I don’t want to be too negative here, so I will say these things with the caveat that TEFL is for many people an immensely rewarding job. Be realistic about yourself and your expectations and try to get some experience.