Shane, who says he leads AI evaluations for the data science team at a legal-tech AI company, argues in this free workshop that AI evals should not stop at quality scores. His framework, the "AI impact chain", links a feature change to AI quality, then to customer value, then to business impact, and he ends on causal inference as the method that turns a customer-value gain into a revenue forecast. Once the relationships along the chain are estimated, an offline eval run that takes minutes can be translated into a predicted dollar impact for investment and prioritization decisions.
Three levels of maturity. Level one is shipping blind: no quality metric, so quality feedback arrives as qualitative complaints from the unhappiest users or as churn. Level two is quality-confident: quality improves offline, but nobody knows what it did to users or revenue. He says most current eval content and courses take people from level one to two, and that level three, tying AI improvements to business outcomes, is rare even at large companies, which reach it for some features only.
Why each link is needed. He groups quality metrics into correction rate (how close the output came to what the user wanted), acceptance rate (the share of outputs accepted as-is) and error rate (precision, recall or F1 on annotated failure categories, which he likens to MLOps debugging). None of these is customer value, which for workflow products he measures as time to finish a task or task success rate. A quality metric can chase errors users do not care about, or perfection when 70% one-shot is enough. Customer-value metrics can mislead in turn: his own long browsing for a pizza peel on Amazon would look like engagement but was confusion. Revenue on its own invites false credit; at Nextdoor, he says, engagement spikes that teams claimed for their launches were repeatedly Texas ice storms.
The worked example. A team decides whether to roll out V2 of a text-to-SQL AI analyst, sold at $200 a seat a month and live for 5% of users. V2 adds a planning step, schema context and a second agent that validates and repairs SQL, at higher compute. Latency rises from about 30 seconds to two minutes, but re-asks fall (from about 2.5 per query in V1) and edits per query drop from 2.4 to 0.3, an 87.5% reduction. He posits quality splitting by segment, better on customer-support questions and worse on finance, so the two teams would disagree on shipping. Customer value breaks the tie: time from question to chart export falls from 12 minutes to 3. Repeated A/B tests, he says, eventually show with statistical confidence which quality metrics drive customer value, though he insists AI quality metrics remain the guardrail before anything reaches customers.
From customer value to revenue. Because business impact lags by months or quarters, teams ship on customer value and use business impact to decide where to invest. A/B tests are the gold standard of causal inference, but regression-based methods such as difference-in-differences or propensity score matching also work. In his explicitly made-up example the model yields five extra seats per account per minute saved; 9 minutes saved gives 45 seats per account, 4,500 seats across 100 accounts, $900,000 in added MRR and about $10.8 million ARR, with an interval of roughly $8.6–13 million. That coefficient, he says, is the crucial number; the rest is arithmetic.
Questions from attendees. With too few users or a risk-averse industry he suggests backfilling about six months of quality metrics and running causal inference instead of, or ahead of, an A/B test; with no users at all, focus on quality and qualitative research. When leadership cares only about latency and cost, agree guardrails up front and reframe later debates around ROI. Structured output suits completion and acceptance rates, he says, while chat and multi-step agents need more error analysis. On tooling he finds eval platforms good at traces and scaling judges but weak for annotation, and recommends vibe-coding annotation UIs that mirror the product, such as redline diffs or a live chat pane. He names instrumentation, agreeing on what customer value means and annotation tooling as the main bottlenecks, and says his own pipeline took three or four months before it paid off.