Capital investments are what some may call research and development and/or capital assets such as buying machinery or equipment. The truth is, the company that is most efficient will be able to reduce costs, with reduced costs they can lower prices, lower prices lead to increase demand, and finally increase in demand leads to an increase in market share.
For example, 1from 1865 to 1870, Rockerfeller's Standard Oil company dropped the price of kerosene from 58 cent to 26 cents per gallon and made profits each year. Some oil producers were unhappy, but American' consumers were pleased that Rockefeller was selling cheap oil. Due to Rockerfeller's efficiency he was able to lower costs, reduce prices, out compete his competitors, and eventually rise to monopoly status.
However, not all monopolies are good (confusing right?). Some monopolies are actually harmful and bad for consumers and the economy but these monopolies are what some will call government sponsored monopolies. Government sponsored monopolies are companies that are subsidized by their government. In other words, companies that are being paid for by tax payers.
The problem with government sponsored companies is they tend to be very wasteful and make bad business decisions. When a company does not need to use their own money to make investments or operate they do not care for loses. In fact they continue to operate at a lost knowing they will receive additional money from government.
What usually worst about government sponsored monopolies is they tend to lobby with the government in order to regulate and restrain the more efficient companies of their business, causing consumers and the market to pay for the extra costs of bad and inefficient products and services.
So in truth, private monopolies are good, hell even monopolies in MMOs are good. If i can purchase my goods from a player or business who is selling well below market price I am happy because the lower the price means the less time I need to spend farming or working for the goods and services. Therefore; my standard of living rises as I now have more leisure time to focus playing or doing the things I enjoy. So please, lets encourage private monopolies because fallen consumer prices will greatly benefit our society.
1 The Myth of the Robber Barons by Burt Folsom, Location 1466 - Kindle Version