NELL Founder: 300 Prototypes to Attack Japan's ¥22 Trillion Sleep Debt

Morght CEO Hiroki Doi recounts going from 10 failed apps to 300+ pocket-coil prototypes to build the NELL mattress — joined by sleep physician Yasuhito Nakatomi on the medical case for improving sleep quality.

• Japan loses an estimated ¥22 trillion per year to insufficient sleep — roughly ¥300,000 per person annually
• Doi founded Morght at 21; after every app flopped, he pivoted to mattresses. NELL has sold 220,000 units and now clears over ¥200 million in sales per day
• A NELL double uses 1,734 pocket coils — roughly double the count of a typical luxury hotel mattress. Doi iterated through 300+ prototypes varying coil wire diameter in 0.1 mm increments before settling on 1.2 mm and 1.3 mm
• Soft mattresses popular in retail stores impede natural turning during sleep and cause mid-sleep waking. NELL is designed with responsive rebound to support natural repositioning
• Compressed packaging, D2C sales, and in-house advertising cut shipping costs and middleman fees, letting NELL double the coil count while keeping prices competitive
• Only 54.5% of Japanese adults get sufficient sleep time. The Ministry of Health target is 60%; the sleep-restoration satisfaction rate is currently 78.3% against an 80% goal
• The three root causes of poor sleep quality are duration, rhythm, and depth. “Social jet lag” — catching up on sleep on weekends — disrupts the circadian clock
• NELL offers a 120-day return and full-refund guarantee plus a 10-year quality warranty to lower the purchase barrier

2026-04-27 · Watch on YouTube

Japanese page: 日本の睡眠負債22兆円に挑むNELL創業者