HN user
The criteria for failure at Google is very different from that for a startup.
For eg. Allo was considered a failure because it had 'only' 10 million DAU in first 8 months. For a startup that would be like hitting a jackpot.
The performance of my team's application at Myntra (Bangalore) was badly affected by foreign keys on MySQL and we decided to drop them.
The trick we used was to drop them only in production, not in test environments. In test environments they acted as guardrails to ensure that our application did not break the constraint.
So in a way it gave us best of both worlds