In former days, and still, many businesses had departments, each with their own procedures and systems.
We call that 'silos'. A customer request has to go through one or more silos with invisible but strong walls. Each department described its own processes in process documents in Word, Powerpoint, and so on. The successive links in the overall process are not immediately visible. An overview of the overall process is difficult to visualize. This complicates the transfer of work from one process step to the next.
Process management works from a customer-focused perspective. The customer must be served as quickly and properly as possible. From customer request until delivery and payment is seen as one company-wide process, with company-wide terminology and rules. The entire process chain is seen as 1 integrated process.
In the company-process itself the end-to-end customer request travels along several disciplines, e.g. ordering, production, delivery, payment.
See also Process Maturity.