Use case:
Creating a few donut charts for completion status over different sections of the project. Some sections have both complete and incomplete tasks, while other sections have only incomplete tasks.
The problem:
Donut chart for section with only incomplete tasks will use the same color for incomplete tasks portion that is used for completed tasks portion in other donut charts. This makes dashboard harder to read — it looks like all tasks in the section are complete, but the situation is the opposite!
Suggestion:
Always use the same color for Completed and Incomplete tasks in charts.