Faced with the rise of AI, cofounders Josh Miller and Hursh Agrawal realized that incremental updates to Arc wouldn't suffice—they needed a fundamental reinvention. Despite strong user attachment and internal uncertainty, they pivoted to build Dia, an AI-native browser designed around a personal intelligence layer. Guided by a prototype-driven culture and a philosophy of 'assume you don't know,' the team rearchitected their technology to enable memory, context, and adaptive assistance. Early setbacks, including nearly launching without a core memory feature, were overcome through iteration and conviction. Today, users are organically building custom workflows, turning Dia into a dynamic, personal space on the web. Rather than competing on specs, the team draws from romanticism and human-centered design, prioritizing emotional resonance over technical mimicry. Their bet is that the future of AI lies not in replicating humans, but in creating interfaces that feel meaningfully connected to how people think, feel, and create.