When the font size is all the same and colors are competing, the viewers' attention cannot find a clear visual path.
Do's - Hierarchy
Font size and boldness and color choice combine to create a visual path to support the title.
Don'ts - Scale
The slices don’t add up to 100% here. Most likely, the survey would have allowed multiple choice. In that case, a pie chart is not the right choice.
DO's - Scale
When presenting parts of whole, make sure all parts visually add up to 100%.
Dont's - Readability
When visual clutter dominates the chart, viewers can spend more time trying to visually organize the clutter than interpret the data. Avoid 3D charts as they are generally found to be hard to read.
Do's - Readability
By eliminating unnecessary words or visuals and using concise, accurate language with fonts that are easy to read, the viewer can easily focus on the data.
Don'ts - Color
By using competing colors in the chart, the viewers’ attention may be jumping back and forth between sections instead of focusing on the main data story.
Do's - Color
Use color of equal visual prominence. Non-text contrast ratio of at least 3:1 is suggested for accessibility by WCAG 2.1. (See References & Resources > Accessibility & Color to learn more about color and accessibility.)
Dont's - Axis
Base placement of section on 0 or 90 degree rule, not on personal preference.
Do's - Axis
Start at 0 degrees or 90 degrees.
Compare with Stacked Bar Chart
Stacked barchart can also be used to show parts to whole comparison. However, it is better suited to show change over time.
Pie charts are helpful when sum of parts add upto a meaningful whole.