In January, 2017, the market capitalization of all public companies headquartered in the United States of America, exceeded $25 trillion dollars, in which, market capitalization of these companies, represented the total dollar value of each one of these company's outstanding shares. While there are myriad reasons why companies file to go public in the first place, fundamentally the primary reason is to more easily and more readily raise money for future growth as well as for present-day operations through the sale of and the purchase by outside monetary investors of their stock, which will be traded publicly on the stock exchange that will allow for liquidity, price appreciation, and dividends for those investing in such. Another very important reason for becoming a publically traded company is so that insiders, other highly placed executives, and important personnel, can now more easily monetize their compensation packages which typically would include stock options and stock bonuses, making it far easier to both retain valuable personnel as well as to entice new highly valued personnel to work for the company, because stock publically held, is both liquid and easily valued because it is publically traded, as opposed to companies that are privately held, which while also being able to offer stock options and stock shares, ultimately control that value internally which may not reflect the true value of those options or stock shares.
Another very valued reason for companies going public, is that capital is truly the engine that makes a company grow, that is to say, great ideas, even great managers, and great businesses, may not be successful, and often aren't nearly as successful as they could be, if they lack capital or are starved of capital, for without working capital, and plenty of it, the necessary funds for research and development, for the compensation packages needed to entice the best and brightest, as well as retaining executive teams and highly valued members is problematic. This means, that companies that have a viable business model and have been either able to prove that in actuality, or are able to lure investors in by their potential, often are quite motivated to put themselves into the position of going public, in order to juice that growth, take market share, and to become a true force in the marketplace.
Going public though, is definitely a two-edge sword for any company, for not only are there rules and regulations for publically held companies on a given stock exchange, but the investors in the stock of any public company, are by nature, interested essentially in their investment, making them money over time, which comes through continued profitability, growth, as well as dividends, and those companies that fall short of quarterly goals and objectives are punished for their failures. So that, public companies, most definitely feel the pressure of trying to achieve what is expected of them, so that quarterly projections, yearly goals, and so on and so forth, are disseminated to the public, so that revenue and profit goals are set and thereby are expected to be met or exceeded by such companies.
This then, follows, if we are to take it to the extreme, that virtually all public companies, fundamentally have the exact same desire, which is to take as much market share as possible, as well as to make a reasonable return on their investment capital, so that, the winners in the stock market world, often get bigger, not necessarily by internal organic growth though that does happen, but instead by buying out or merging with competitors or through vertical integration, all in the effort to become the only true player in their field, because once you are the only one that matters, or a consortium of a few that do, you now have monopoly or oligopoly power which is great for those that work for those publically held companies as well as their investors, but means typically that the public in aggregate has lost out via higher prices, lack of options, and even the stagnation of innovation, because the few and the chosen own that market.
This means, in effect, that publically held stock corporations because of their sheer size and the pressure by their investors to get even larger as well as to make more money, become, in principle, a real danger to the people, for when a few public companies dominate their respective domains, then the consumer will be seen more often as someone to be fleeced as compared to someone to be properly served.