What is the difference between offline and online evaluation, and why do you need both?
Offline metrics gate releases; online metrics reveal what actually happened with users. What shows depth is understanding why offline wins routinely fail to hold up online, and how the two feed each other.
Updated Sep 2026 · Grounded in real GenAI, LLM, and AI/ML engineering interview loops and written to a senior-engineer editorial bar.
Offline metrics gate releases; online metrics reveal what actually happened with users. What shows depth is understanding why offline wins routinely fail to hold up online, and how the two feed each other.
Lead with where the obvious approach breaks, because that is the judgment they are screening for — most candidates jump straight to the happy path and lose the room.
Then walk the failure back through the pipeline in order, naming the one metric the customer's exec sponsor actually cares about before you propose the fix.
