When should you throw versus return a Result type?
PICTURE THIS: RAG CHATBOT
Simple meaning
Exceptions are for unexpected failures
WHY — Exceptions instead of guessing?
Why interviewers care about Exceptions:
contrast on Exceptions, not two memorised paragraphs.
the developer, then one case where picking wrong hurts.
Name the idea, why it exists, then one short example.
End with when you use it and one common pitfall.
STEPS — What happens step by step?
Before you speak the answer, walk the interviewer through these steps:
- 1Define it
Exceptions are for unexpected failures
- 2catching them on every
validation is slow and noisy.
- 3For expected business outcomes
I prefer a Result or ProblemDetails.
- 4I still throw when
the program is in a truly invalid state.
- 5Common mistake
What juniors usually get wrong.
- 6Close
When you pick this over the alternative.
EXAMPLE — See it in action
Here's a short line you can speak, broken into clear beats:
Note: Adapt this scaffold to your own project — keep it under 60–90 seconds.
Key takeaway
Exceptions are for unexpected failures catching them on every validation is slow and noisy.