What are some challenges faced when adopting TDD?

Short answer: Initial learning curve and mindset shift. Writing tests for complex scenarios or legacy code. Overhead in writing and maintaining tests. Possible resistance from teams unfamiliar with the practice.

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.