"If you haven't done enough reporting, the story will look like a giant comb-over. Every reader will know you're trying to cover bald spots in your reporting."
The best writers aren't always the best reporters. Those are two different skill sets. Good writers sometimes get a pass from overworked editors, because -- well, because their copy is passable. It reads well. It's free of errors in grammar, punctuation and syntax. But that doesn't necessarily mean the writer nailed the story.
The best reporters find an editor -- even if it's not one they work for -- who will read their stories with a critical eye and then ask uncomfortable questions. What are the missing pieces? The missing sources? What is this story really about?
No writer likes having his or her masterpiece picked apart. Not during the process, at least. But great reporters understand the need for that process, and they appreciate it later when the final result is so much sharper than the early draft. Every writer needs an editor ... not a comb.