"The breadth of the potential readership is also a factor"

Mark Millar's quote suggests that the possible readership of a work must be thought about when developing it. This means that the author must think of who their work is meant for and how large the audience might be. For instance, if the work is planned for a particular age or market, the author ought to think about how to make the work available to that group. Additionally, the author ought to consider how to make the work interesting a broader audience, such as by using universal themes or topics that can be taken pleasure in by a variety of readers. By taking the potential readership into account, the author can produce a work that is both enjoyable and accessible to a wide variety of readers.