A more thorough explanation:

Self-dealing is when someone who has a responsibility to act in the best interest of a company or organization instead takes actions that benefit themselves. This can happen when someone with a fiduciary duty, like a board member or executive, makes decisions that benefit themselves instead of the company they represent.

For example, imagine a CEO of a company who decides to award a contract to a company they own, even though there are other companies that could do the job for less money. This would be an example of self-dealing because the CEO is putting their own interests ahead of the company's interests.

Self-dealing can also happen in the stock market. For example, if someone buys or sells stocks based on information that is not yet public, they are using insider knowledge to benefit themselves. This is also considered self-dealing because they are not acting in the best interest of other investors who do not have access to that information.

Self-dealing is not allowed because it can harm the company or organization and the people it serves. It is important for people in positions of power to act with integrity and always put the interests of the company or organization first.