That's actually me, the bad editor. I can write and rewrite until my face turns blue, but editing stumps me sometimes. Self-editing books are available to help develop or learn the basic skills. Yet, editing takes practice and a keen eye to details. I can't say these are my best writing attributes, so I must rely on others to assist with the editing.
Now, I can write a fair story and engage the reader enough that they will want to continue flipping pages to find out what happens next. My failing as an editor is apparent when it comes time to polish the work so that the reader doesn't have to wade through unnecessary or misspelled words to get the story.
I do have a copy of Line-by-Line, Strunk and White, and of course Webster's Compact Writers Guide to help me with the technical aspects of writing. Still, it's the actual sit-down time in front of the pages that gets me every time. I recently read a passage from a previous work and noticed I completely missed a word that was spelled incorrectly. How in the heck did I manage to skip over that one word? Was it lazy eyes from reading and editing a dozen times or was it simply poor editing skills?
So today, I am spending a little more time going over my work to see if I can catch any additional mistakes. Hopefully, as I practice editing, my skills will improve to the point where my finished product is saleable.