What kinds of elements do you consider when thinking about what makes a successful essay?

Comment on the following
What kinds of elements do you consider when thinking about what makes a successful essay? After listing some of those attributes, how does your “most successful” essay match up with these elements? In what ways does it fall short?
What have you learned about the writing process? What is your writing process? How has the emergence or, at least, definition of that process changed how you write, if at all?