At a recent writers' conference in New York, I was asked by someone in the audience to give my best pieces of advice. Thinking fast, I ended up throwing out four tips. One of those tips was "Don't put all your eggs in one basket."
In my mind, if you have written only one novel or memoir, you are setting yourself up for disappointment.
At any given time, I have from 3-8 different projects going on. That includes articles due, articles turned in, book proposals to my agent, book proposals in progress, or new plays I'm trying to get produced. Something is always cooking. Besides having multiple rounds of "good news" with so many projects, it also allows me to never have writing downtime. It's not like I send out 10 queries and say, "Well ... nothing to do now but wait for agents to respond, I guess." Nope - none of that. Something is always cooking, and I enjoy the variety.
In addition, as an agent said to me recently, a lot of first novels really aren't that good. This is a hard fact of life. If you spend 6 months or a year on a book and it turns out bad, it's not the time to quit. Start the next one. Writing gets easier - and you get better at it.
Diversify! Nothing bad can come from it. If you start writing articles, for example, that means more bylines (awesome), more credibility and platform (double awesome) and more money for writing the pieces (triple awesome).
On a side note, I apologize that it took me several days to finish this darn post. I was sick and then traveled to Georgia for a writers' conference. (I'm at St. Simon's Island now. Of course, if you were my Facebook friend, you already knew that!) In the interim between the start and finish of this post, I see agent Scott Eagan posted with his own take on the subject.