Sometimes you just know there's something wrong with a story, and you realize, too, that you cannot, for the life of you, figure out what the hell the problem is. This bothers me. But there's no reason to fret or toss that bad boy in the dreaded virtual "trunk." Why not send it a few people to read? They may pinpoint the issues you've been too blind to see, or reaffirm your fear that the story indeed sucks ('cause let's face it, some stories need to be taken out behind the shed and put out of their misery).
I rarely send my work to beta readers, but after having a few people read my latest short novel I am a believer. Having several pairs of eyes going over the story is nothing but helpful, and why wouldn't a writer do everything they could to improve upon their story before submitting the manuscript to a publisher?
I also think it is important to have a variety of beta readers if at all possible. I had three for the short novel I am referring to, one of which isn't a writer. Though he liked the book a lot, he gave his two cents and pointed out several issues. The next reader was a writer himself and wrote a very detailed critique that, when I get around to completely rewriting the first half of the story, will come in very handy. Some of what he pointed out was so obvious and braindead that I'm shocked I disillusioned myself into thinking it would work. There's one more reader out there, and I look forward to her thoughts.
I am beginning to realize the importance of beta readers and I appreciate those who are willing to take the plunge. It means a lot to me that there are people who will spend their precious time reading my work and offering their thoughts. It has proven to be quite helpful. I am looking forward to the rewrite and I'm certain it will turn out 100% better than my first version.