Google Play's requirement for a minimum of 12 closed testers for new apps often raises questions. Is there a scientific reason behind this specific number, or is it arbitrary? The answer lies in usability research and statistical insights.
Industry research, notably by the Nielsen Norman Group, suggests that testing with 5 users typically uncovers about 85% of usability issues. While this sounds low, the curve of discovering new issues flattens significantly after the initial few testers. However, for critical issues and broader compliance, a slightly larger pool provides more confidence.
Google's choice of 12 testers likely aims for a balance between achieving robust feedback and making the requirement attainable for developers. It's enough to:
While more testers might uncover minor, edge-case issues, 12 testers for 14 days is seen as an efficient sweet spot for ensuring a stable and user-friendly initial public release without imposing an excessive burden on developers. It's about 'good enough' to significantly mitigate risk.