It literally just (1) keeps printing money for investors and (2) keep some people employed. Ambitious people will take the mantle every 15-20 years and do more of 1 and 2 until they make a mistake.

The goal of a successful company is basically serving those two sets of people, Google may enter the retail market or real estate, or McDonalds will take over Cloud Computing -- they're all just trying to get a consistent return.