The experience or skill level of your voice talent is a large factor in determining the amount of editing needed to produce a piece. Accuracy with reading copy and breath control are key to easy editing, as these are the two main parts that require the most extensive editing. Removing a mistake in a read is quick, since the reader can just pick up right where they left off. De-breathing requires a little bit more finesse. When we breathe during normal speech, it creates space. Often, this is what separates one thought from the next. Many times in a voice project, this space is still necessary, without the breathy sound, of course. For a book or educational project, that space allows the listener time to comprehend and take in what is being read. In other instances, like a commercial VO for example, much of that space is removed to accommodate for a time limit or requires information. The all-important question is, "Who's listening?"

Listening in the recording and editing realm is important to keep in mind. Our ears hear what is in our environment, but we choose what we listen to by where we place our attention. Microphones, however, do not discriminate. They pick up everything. Every breath, sniffle, shuffle and extraneous room noise are picked up by your microphone.
This is where the trained ear and technical expertise of an experienced sound editor can be advantageous. It is important to know what to listen for. Another simple editing tip is to take what you do want to keep and put it into a new track. This may seem like a no brainier, but it leaves the entire original read if any part of it is still needed.

An experienced editor can be a great asset in completing a polished product. Whether it is someone in your own studio, or someone you outsource your work to, their expertise can be invaluable. Sound engineers have the technical advantage of knowing the software, matching the amplitude (volume) throughout the project, and quickly separating the gems from the coal so to speak.