Information shown in the analysis side-bar
The number of words in each chapter is shown along with a graphical representation of its length. This allows you to quickly identify patterns in your writing.
You must have the setting for analyze by chapters set to 'yes' for this report to properly run.
Why should you care about chapter length?
Chapter breaks provide structure and navigation for the reader. They create suspense and shift the focus of the story from one character, place, or time to another.
I find it useful to take a step back and look for outliers in my chapter lengths. The use of long or short chapters relative to those around them can create drama and or emphasize a scene. However, if the outlier has no purpose or is excessive in length, it can cause the reader to lose interest and kill the momentum of your story.
The bottom line
Use common sense when looking at chapter lengths and keep chapters comprised solely of backstory and detail to a minimum.