The short answer
Because the engines disagree. In our measured runs, a brand cited on one engine routinely fails to appear on another — one engine's answer is not a proxy for the market. Our US rail follows how US buyers actually search: as of June 2026, StatCounter puts Google at 86.67% of US search and Bing at 8.73% — and Bing carries an AI answer of its own — with Yahoo Search at 2.55% and DuckDuckGo at 1.53% kept as secondary diagnostics. And we don't stop at AI answers: every audit tier runs the same questions across organic search, news, YouTube, short-form and Bing Copilot — {{ GRID_FACTS.en.surfaces }} places an answer can appear, counted on {{ GRID_FACTS.en.engines }} engine captures — so you can see whether your search equity is transferring into AI answers.
Why this matters
Judge from one engine and the gaps opening on the others never reach the report. Drop the engines your buyers actually open and the read misses the market it was bought for.
Fifteen engines run in one round and produce seventeen surfaces. Strong places and empty ones land in the same table.
Questions buyers read next
Where this answer comes from — Published pricesHow we measureTerms, defined