P&G was losing market share as parents transitioned between diaper sizes. While their sales data showed a problem, it did not explain why. Through mobile and digital qualitative research, P&G was able to gain insights into the human behaviors and motivations behind the data trends. The research involved observing mothers in real-time as their babies moved between diaper sizes via smartphones. This revealed that mothers would switch brands or go back to a smaller size due to fit issues. Armed with this understanding, P&G developed new sizing and shelf solutions to keep mothers and babies happy.