What's the hardest "skill blend" to pull off in Web3, and why do so many projects fail at combining them?

​We’ve all seen it happen:

​A brilliant dev team builds incredible zero-knowledge infrastructure but nobody uses it because their onboarding is impossible and their docs read like a PhD thesis.

​A genius marketing team builds an insanely hyped community but the product breaks on mainnet because the smart contracts weren't audited properly.

​Real community building in Web3 feels less about pure hype and more about cross-pollinating opposite skill sets.

​For those who have worked on or contributed to projects: What is the single hardest pair of skills to blend successfully in a team?