Someone wants to have his house built. He roughly draws out the building plan. He then sends out the word that he's looking for a builder to construct the house for him. Some time later, he finds a long queue of people lining outside his place. Any one of these people can build him this house, they're all qualified builders. How would he know which one is best suitable to build him the house the way he envisioned it? The one who can read the plan the way he has written it is more likely to do the job correctly.
