When using the Comments & Ratings Combination step, reviewer must enter some text in the comments box, as well as provide a rating for each criterion.

To clarify this to reviewers, even if comment or ratings are optional for your process:

• Provide additional instructions in the Routing Steps informing reviewers that they can simply enter "N/A" or "NC" in the comment box if the reviewer has no comments. 
• Similar types of instructions can be provided for ratings. Administrators can instruct reviewers to select any number in the rating scale, or include "0" on the rating scale as the null choice.

Administrators have also gotten creative with the Build My Own Form  or Form Designer routing step types, using multiple choice questions as rating scales and text boxes for comments, both of which can be made optional.