The only way for a company to remain "dominant" without doing a good job is for it to curry special favors from the government. This is done usually by lobbying

The only way for a company to remain "dominant" without doing a good job is for it to curry special favors from the government. This is done usually by lobbying for regulations that harm competitors, while leaving the company relatively unharmed (differences in scale following consolidation are natural, for example, but additional regulatory burden will keep small upstarts from entering the market - think about the way milk is sold in California). Without regulatory assistance, unearned monopolies are impossible to maintain.