As I mentioned before, I just reentered the world of critique partners or beta readers (whatever term you prefer). I will admit freely that I was nervous about this, because of past experiences (from long, long ago, LOL). As usual, what I am most nervous about ending up being something that I shouldn't have been nervous about at all. I was paired up with a lady via one of my RWA chapters and got back a critique of my first couple of chapters from her like the day I emailed them to her. :-) And, the good news, she confirmed everything I had been worried was wrong with the thing. Not that it's awful, but that the story could be so much stronger. As I was reading her critique and the spots she marked as wanting to know more I found myself nodding along with her in complete agreement. Why? Because I had already suspected these problems, but wasn't sure if they were real problems or just the general "this sucks" that most writers feel when they read their own work.
It is not a closely guarded secret that we as writers are horrible judges of our own work. We can edit and edit and edit, but it's all too close to us for us to see where the real problems are and where we think there is a problem but there isn't. Dean Wesley Smith recently did a great post on this. Pay special attention to Rule #3 which addresses this issue very well.
Another problem with not being able to clearly see where there is a problem, you can edit out the great parts from your book, because you really are not the best judge of it.
Do you have a critique group, critique partner, or beta readers? Do you think they have helped or hindered your writing (yes, they can actually do the opposite if you aren't careful)?