Listed companies are those companies whose shares are listed on a recognized stock exchange for public trading. When a company’s security is listed in a recognized stock exchange the price fluctuation can easily be observed by the investor and he/she can easily determine the increase/decrease in value of their investment in a concerned listed company.
This is the only reason that the volume remains high in the case of a listed company as all the moves can be observed and investment strategy can easily be planned in that company.