What was one of the problems John D. Rockefeller encountered in the petrolem business?

One of the significant problems John D. Rockefeller faced in the petroleum business was intense competition from other oil producers. This competition often led to price wars, which threatened profit margins. To combat this, Rockefeller implemented strategies such as forming the Standard Oil Trust, which allowed him to consolidate control over various aspects of the oil industry and create a monopoly, ultimately stabilizing prices and increasing efficiency.