"I wrote two plotted books, got some of the fundamentals of storytelling down, then... it's sort of like taking the training wheels off, trying to write a book that's fun in the same way without relying on quite such mechanical or external beats"

In this quote, author Jonathan Franzen is discussing his composing procedure and how it has evolved in time. He mentions that he has actually written two books that were carefully planned out, permitting him to master the basics of storytelling. Nevertheless, he then compares this to riding a bike with training wheels - it's safe and structured, but not necessarily as enjoyable. Now, he is challenging himself to compose a book that is still amusing, but without counting on the same mechanical or external methods. Basically, he is pushing himself to end up being a more knowledgeable and innovative writer, instead of relying on formulaic techniques.