Isolation: Microservices need to ensure that one service's operations don't conflict?

Short answer: with another's. Achieving this isolation in distributed systems can be challenging because services often depend on shared data that needs to be consistently updated.

Real-world example (ShopNest)

ShopNest splits Catalog, Cart, Order, and Payment into services so teams can deploy catalog changes without redeploying payments.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.