These businesses exist and operate the way they do because of customer desires. The customers could hire better agencies but for a number of reasons don't.
Sorry but saying that it’s “customer desire” is nonsense. Most customers don’t have the skills to judge the work they receive. They know they need something done. They trust someone. How are they supposed to know if what they got was subpar? It’s like that in every profession. You have to trust that the person on the other side is professional and more often than not they’re not.
