Understanding how large systems work is very difficult, but is a major part of really being able to navigate an industry well and lucratively. For example, the garage door company and garage door repair industry is a complex system with not only laws and regulations, but also complex hierarchies of companies and services. It's not unlike a world government. In fact, you can use that analogy to try to begin to understand the complex system.
There is always the head of a company, the CEO, which stands for the Chief Executive Officer, and he or she is in charge of making all of the executive decisions. So it seems like a company's actions are mostly based off the wishes of the CEO. But that is not entirely the case- many things can influence the CEO and the board of directors in the background. Investors can force a CEO's hand in terms of what kind of research and development the company will engage in. If they don't have funding they can't do certain research. Other things also affect a CEO's decision-making process.
Politics can do that. For example, how laws change can affect the ways companies are allowed to manipulate or rip off clients. Safety and quality laws of products change, and these change at the behest of politicians. Therefore, it behooves really big and (sometimes nasty) companies to lobby or push for law changes that are in their favor. They can do this through legal lobbying channels, and sometimes not so legal ones. Like under the table deals and bribes and blackmail.