If I think writing a novel is preferable to writing a screenplay, or vice versa, then I may have the desire to pursue one of those literary forms, or both, if so inclined. To pursue the screenplay or the book requires careful research as to how to proceed, so I can consider the cost of proceeding. Knowing how to proceed, knowing the realities of the market, then I decide if I should proceed and ask questions like: Is it worth proceeding? Does one have the time? Does one make the effort?