Placeholder. The single most 'innovative-sounding' feature in the entire diaper category — the wetness indicator strip — is actually 20-30 years old and now completely universal, meaning most of what brands market as 'innovation' in this specific feature is really just table-stakes maintenance.
What we've found so far: Found in some form on nearly every taped diaper across all 12 markets researched; several brands still describe it with fresh, innovation-toned marketing language despite zero underlying change.
Open research: Trace exactly when the first wetness-indicator patent was filed; find whether any brand has tried a genuinely new mechanism (e.g., smart sensors) to replace it and why adoption has stalled.