Positivity or death
I hate Debbie Downers for a very practical reason. To create something new on a regular basis, like a professional, you need to maintain a minimum level of positivity.
You cannot work on a novel (a new business, a new product etc.) if you don't believe (or hope) it can be successful. In the beginning any new venture hinges on irrational belief of the writer (founder).
When a Debbie Downer comes along and starts to present fact-based criticism of the novel (or business idea) the writer (founder) may get doubts as well and stop working.
The thing is: There is no such thing as a well thought-out business plan for a company or a novel. Larry Page and Sergey Brin didn't have a business plan when they created Google. They built the technology first and later, when it turned out that Google was better than any other product, they began to search for a monetization strategy.
A Debbie Downer may have told them that it doesn't make sense to create a search engine in a niche with at least 4 well-established brands (AltaVista, Lycos, Ask Jeeves, Yahoo).
If Google founders listened to such people, there would be no Google today.
Also, I don't like Debbie Downers as human beings. Most new books suck and most new businesses fail. It takes brains and balls to attempt to succeed where most people fail.
Debbie Downers surrendered to the fact they lack brains and/or balls to do something new. In order for them to stay calm the need everybody to give up on innovation. This is their motive for discouraging beginning writers (entrepreneurs) with their cautionary tales (which are in reality just wishes for failure).
I am here to create something new, to do the best out of the finite resources I have. If you choose to pretend that life is miserable, that we the people have zero control over our lives, that's fine. In this case, please find a web site which is more in line with your beliefs and your choices.
Read about my other values here.