Because of writers who are willing to do a blog post on Fiverr for $5 or marketing copy on Upwork for $10, the rest of us spend unnecessary time explaining to prospective clients why a $200 blog post should be worth it for them.
You did the work and you did it well. You provided any revisions or changes the client asked for. Then you wait. And you wait. And you wait some more. What do you do when the client won't pay?