It happens to me all the time. At first I thought I was being childish and snob, but it's what it is. I don't enjoy knowing too much about my own story.

At some point Stephen King says something like this: "I'm the first reader of my own story and if I'm interested in the flow of things, then most likely some other person will also be interested."

It's very true, because when I plot into the very small details, I feel like the story is already finished in my head, and there's no point to to write it.