Actually there is, and that solution is by hiring a ghostwriter. Not only do they give you the extra hands that you need, which increases your book output, but you know that each piece given to them get's completed. - Thus punching a hole in any limit that used to be on you.
However, nice and all as that sounds, it also bring it's own problem. And that's both of you being on the same page.
Just like the children's game, Chinese whispers, the message can sometimes get distorted on the way to completion. - Meaning that the idea you thought you gave your ghostwriter isn't the book you get back.
When this happens, it can mean hiring another ghostwriter, trying to fix it yourself, or giving up on the idea completely. All of which means you've lost time, money, and are no further on than you were before.
If only there was a way around all this? Something that could not only guide you to hiring the best ghostwriter for the job, but that could guarantee that you got the type of book you want written. - Even if you never hired a ghostwriter before.