6 lessons I learned watching a robotics startup die from the inside

A former COO of K-Scale Labs, a YC-backed robotics startup, shares hard-learned lessons after the company failed to secure Series A funding and shut down in late 2025. Rui Xu identifies six critical mistakes that killed the humanoid robot company, including dangerous over-reliance on AI models instead of basic hardware safety features like mechanical joint limits, treating complex supply chain operations as simple tasks, and rushing with unrealistic timelines that led to corner-cutting and broken promises to manufacturers.