The core principle: technical metrics mean nothing to a customer until you convert them into dollars or time. An interviewer playing a business stakeholder doesn't care about Hit@5. They care about headcount and revenue.
Value = Volume × Per-Unit Savings × Adoption Rate
Every ROI story you tell plugs into this. Let's unpack each term.
Volume — how many times does this thing happen?
"We process 8,000 tickets a month."
Per-unit savings — how much time or money does one instance cost today, and how much do you cut it?
"Each repetitive ticket takes 12 minutes of agent time. AI deflection cuts that to 0 for 40% of tickets."
Adoption rate — what fraction actually gets captured by the solution?
"Assuming 70% of deflectable tickets actually get deflected."
Then you convert to dollars:
8,000 tickets/month × 40% deflectable × 70% adoption × 12 min saved × (agent loaded cost ~$0.75/min) = ~$16,000/month saved → ~$190K/yr
That's the chain. Every number is an assumption — and that's fine. You state them explicitly, which is what a good consultant does.
Think of it as a ladder. You start at the bottom (what you built) and climb to the top (what the business cares about).
Level 1 — Technical metric: "30% reduction in hallucination rate"
Level 2 — Business metric: "Fewer escalations to human agents"
Level 3 — Dollar value: "~1 FTE saved → ~$80K/yr"
Most engineers stop at Level 1. FDEs are graded on reaching Level 3.
The transition phrases that get you up the ladder: