People: Processes require people with the correct aptitude and attitude. This is why breaking down of tasks is so important. In a process driven organization, you can arrange for an unskilled person to do the mundane jobs while a skilled person can be deployed to do the important jobs. Matching skills with task requirements brings down costs and increases efficiency.
Raw Material: Raw materials need to be made available in a timely manner and at least costs. There are companies which have built procurement processes as their core competencies.
Information: The correct information needs to be made available to all the entities in the process. The worker must have the skill and must be well versed with the procedure. The manager must get continuous feedback to ensure that the production is on target and as planned.