There are several reasons people get promoted, including their performance, the length of service, connections and the fact that they are at the right place at the right time. The first and strongest reason for someone's promotion is the achievement they have done at work. It is a common sight that a top sales person becomes a manager of the office. Promotion is a form of rewards with better salary and benefits, which competent employees deserve. Secondly, many companies in Japan promote loyal employees gradually. In fact, it is still considered normal in Japan to work at the same company until retirement. Freshmen start with assistant tasks, and as they stay longer, the more responsibilities come along with higher titles. Third, connections cannot be forgotten as a factor of promotion. Small businesses may hire family members or relatives as a manager or an executive. Additionally, I think corporations invite senior advisers for their networks. It seems common that retired CEOs or high rank officers are welcomed for an advisory position with large remuneration because they have extensive business connections and know key figures in various industries, which will bring business chance and success to the company. Finally, it is also important to grab luck. Job openings happen anywhere, anytime for new projects, predecessor's leave, organization restructuring and so on. So, it might be a good idea to let management levels know that you are here, eager to take oppotunities. I like an idea, called Planned Happenstance Theory which suggests carrer develops in an unexpected way and people be prepared for new adventures. In conclusion, the reasons for promotion vary from a track record to sheer luck. I think it is important to keep learning, stay alerted for trends and be positive.