Caveats — every cross-vertical figure is vendor-sourced; quarantine + bias notes

Honest gaps:

1. The rank-ordering is Industry-consensus, not Verified. It synthesizes convergent vendor datasets; it is not a measured competitiveness index. No such index exists.
2. All quantitative cross-vertical data is vendor-sourced and quarantined. CPC, KD, review bars, and ranking-factor weights all carry commercial incentives and selection / survivorship bias toward active digital participants.
3. CPC ≠ organic difficulty ≠ local saturation. Conflating them is the most common analytical error; real estate is the clearest example (low CPC, brutal organic, Zillow-dominated).
4. Content/SEO maturity (Q6 of the brief) is the thinnest-evidenced axis — largely Directional-Speculative from agency commentary — yet the most decisive for "can a well-built entrant win." Flag it as judgment, not data.
5. Recency/volatility. CPCs and ranking factors shift yearly. Tiering needs an annual refresh.
6. Geography: most data is US-centric. Canadian-specific competitiveness data is sparse; the strongest Canadian signal is lower digital maturity (Canada — 92% use digital tools but only 10% fully integrated (CFIB 2025)).
7. Within-vertical variance can exceed between-vertical variance. Tiers must allow sub-segmentation or they will mislead (Rule — In hyper-competitive verticals, allow a sub-segmentation question).

Quarantined vendor sources: WordStream/LocaliQ (PPC vendor); Semrush (SEO/PPC SaaS); Ahrefs/Moz (SEO tools); SE Ranking, Keywords Everywhere, SpyFu, Serpstat, Mangools, Ubersuggest; Digital Position, Envoca, Focus Digital, Ryze, WebFX (agencies republishing); BrightLocal, Uberall, Sterling Sky, GatherUp (local SEO); Local Falcon (rank-tracking); Whitespark (local SEO software, Edmonton); SOCi (multi-location marketing).

Non-vendor / higher-trust sources used: Pew Research Center, Michael Luca / Harvard Business School, Northwestern Spiegel Research Center, US DOJ v. Google trial, Statistics Canada / ISED, CFIB, BDC.