Starting a business as a doctor means starting a journey to a new life and taking risks. If a doctor considers the advantages and disadvantages of doing business, he or she has advantages over others because he or she is a doctor, but there are also many disadvantages. The advantage is that you can get various ideas from expertise and clinical experience. For example, there may be patents with high entry barriers. However, I think there are many disadvantages as well. The problem is that many doctors fail to overlook them. First of all, there is no opportunity to learn about management in the medical education process. Medical knowledge and management know-how are completely different worlds. Just because you're a medical professional, you shouldn't think you're going to be a successful manager. Peter Drucker, who is called the father of management, said that if someone invests in a company, it is less likely that it will fail to invest in the person responsible for the business than in technology. In other words, no matter how special a technology or patent is, the person's ability to produce it as a management performance is more important. Even if doctors have great ideas from clinical practice, it means that if management is not supported, the business is likely to fail. The second disadvantage is that doctors should spend most of their time treating patients. You should get out of the illusion that you can make grow your business while maintaining your own time for medical practice. If you believe in ideas and think about business easily, you will most likely fail. Failure of a business can result in not only losing money and time, but also losing your precious relationship in the worst case. There are definitely advantages of starting a business as a doctor. I just emphasized that you shouldn't overconfident about them. Therefore, you don't have to be disappointed just because there are more disadvantages than expected. If you think about starting a business as a doctor, I recommend you to make a decision after asking yourself serious questions. The first question is why am I going to do this business? This is a question about ‘finding meaning’. If "make money" is simply for the purpose, it is often given up without overcoming difficulties in the process of building a business. In particular, it is easier for doctors to give up their business because they can think that they can go back to their main job. But if that's what you really want to do and it's a 'meaningful' thing that makes your passion boil, you can overcome any difficulties. And if your business has a positive impact on human society, it can not only arouse your enthusiasm but also the passion of the participating members. The second question is 'Am I ready to use my time?' Just as we have spent countless hours to get a professional job as a doctor, we have to spend as much time as he does to become a successful businessman. The idea that "Because my ideas are so special, the rest of the people who work in the company will make a success" is a big misjudgment. No matter how small the business is, you can't succeed without all-in. You have to use your precious time to get something precious. Moreover, doctors should have a humble attitude to learn about management because they lack more than ordinary people. The third question is 'Am I ready to learn from failure?' No matter how good the item is and how hard I worked, I can fail if I have bad luck. The important thing is not to collapse from failure, but to learn. Even my humble success includes numerous failures that others don't know about. The experience of failing because I didn't validate people and trust them so easily, the experience of failing because I conceited small successes, the experience of failing because I invested in areas I didn't know very well., etc. I've experienced a lot of failures. But if I hadn't tried to learn from those failures, my current small success would not have been. Don't be afraid to grow through failure! I would be more than happy if my humble experience could help junior doctors who are thinking of starting a business.