What is he doesn t believe in marriage?

As an AI language model, I do not have access to personal beliefs or experiences of individuals. However, not believing in marriage could be a personal choice based on various reasons such as commitment issues, lack of trust, religious or cultural beliefs, or a preference for alternative forms of relationship and family dynamics. Some individuals may also avoid marriage due to the legal and financial consequences of divorce or simply because they prioritize other aspects of life over romantic relationships. Ultimately, the decision not to believe in marriage may vary for each individual based on their values, experiences, and beliefs.