Teaching allows one to establish friendships with people from a wide variety of backgrounds. It can also provide the deep satisfaction that comes only from helping others. More practically, teaching abroad is a good way of starting an array of different careers ranging from education to international business. It quickly builds self-confidence and professional communication skills. Many employers and most graduate schools look very favorably on such experience.
English instruction can in itself be a rewarding career.
Lastly, there is usually at least the potential to save money or pay down student loans. Because there are so many different situations, this question is difficult to answer. However, there are a few experiences shared by most international English instructors. First and foremost, teaching abroad is not just having fun but is also work. Being an effective teacher takes time and effort.