A book is a contract between the author and the reader.
The reader agrees to pay X amount of money for a story. The author agrees to provide X amount of entertainment/education/information.
The value of X determines how much the reader trusts the author.
This may be one reason publishing houses are so important. A publishing house has an established, trusted name. The reader can be reasonably assured that any author the publishing house approves can tell at least a passable story.
Trust is difficult to develop. I've noticed as I've given my story out for feedback, and as I've received others for the same thing, trust is lacking. When you ask for comments, the automatic assumption must be that there are comments to be made. That, as a newbie, you don't know what you're doing, and are therefore prone to mistakes of understanding or execution.
In short, a lack of trust.
I am not offended by this. I have recently been reminded to "trust but verify." The one has nothing to do with the other.
I think this is what happened during the contest. The "reader" judges trusted the authors to deliver on their promises. Most readers aren't writers. It would be natural to assume if someone can think up such a story idea, that someone should be able to write about it.
The "writer" judges know better. We know how hard it is to communicate well. We looked for all the little things we try to purge from our own writing because we know how such things can slow the reader down or interfere with understanding or turn a great idea into a mediocre book. How such things can ultimately betray trust.
Trust is difficult to develop, but painfully easy to lose. Betray your readers with a substandard book, and they may forgive you once, but they won't be duped for long.
Writers are encouraged to polish their skills, continually. Our goal is to be the best possible story-tellers we can be, no matter what standard the readers will accept. If we push ourselves, they will come to expect excellence from all authors. That can only be a good thing.