Random House defines culture as the behaviors and beliefs characteristic of a particular group. Corporate culture is the sum of the formal and informal behaviors that a company adopts as their way of doing business. The formal side will include written statements of value, such as respect for individuals, and a written organizational chart. Highly structured hierarchical organizations are quick to reinforce boundaries of position, often slowing processes.
Corporate culture filters through to customers and vendors.
An employee who feels undervalued and frustrated will project that to customers and coworkers. In the former, we may get the opportunity to wait to be acknowledged by a sales clerk while they look up a phone number. In the latter, we may have experienced the down side of the company rumor mill. Either way, we're dealing with people who are aren't giving their best to the business. We get what we encourage.