"9 of 10 web migrations fail" — single-sourced (Numen Technology); use 523-day SEJ stat instead

Claim: "Only 1 in 10 website migrations result in improved search engine rankings. Nine out of ten fail." — widely repeated industry statistic.

Source: numentechnology.co.uk case study (2024-2025), citing unnamed analysis. The 50% traffic-loss figure used alongside this stat comes from the same source.

Confidence: Single-source. Could not be located in any peer-reviewed or government-published source.

Recommendation: Do not lead with this statistic in public-facing Candid writing. Use [[sej-892-migrations-523-day-recovery]] (multi-sample, primary) instead. If the 9-of-10 framing is referenced, attribute it explicitly to Numen and flag it as single-source — don't let it stand as consensus. This is exactly the kind of recycled stat RULE: Every non-trivial claim carries a named source with author/institution + date + URL. Confidence flag honest. catches.