A new Marketing Week study confirms that fewer than half of global brands operate dedicated effectiveness functions, leaving measurement diffused across departments with no single owner when campaigns underperform. The figure — 47% with defined teams — suggests the ad-tech accountability boom of the past decade never reached org charts. Brands still talk attribution while structural accountability remains optional.

The study finds marketers overwhelmingly describe effectiveness as "collective responsibility," a phrase that in practice means no one owns the number when ROAS collapses or brand-lift studies disappoint. Without a named function, effectiveness becomes a quarterly scramble: finance demanding proof, agencies reverse-engineering case studies, CMOs calling consultants when the board asks why $40 million in media spend delivered flat growth. The infrastructure gap is not a knowledge problem. It is a power-structure problem.

This matters because capital allocators — family offices deploying into DTC roll-ups, private equity scanning consumer portfolios, heritage luxury groups defending margin — need counterparties who can answer the effectiveness question in the first meeting. A brand without a Chief Effectiveness Officer or equivalent signals it runs on vibes and last-touch attribution. That limits enterprise value in any transaction where marketing is the moat. Meanwhile agencies pitch effectiveness services into the void, hired by procurement teams with no internal function to interpret findings or enforce changes. The work becomes decorative.

The 53% with no formal function are not small. The study spans enterprise brands with nine-figure media budgets. These are companies that maintain investor relations teams, sustainability officers, and heads of innovation but leave the single largest discretionary spend — marketing — without a performance owner. The asymmetry is structural: effectiveness requires defending unpopular truths (brand takes three years, last-click lies, creative matters more than targeting) in rooms that reward this quarter's performance. Without C-suite cover, the function dies or never forms.

Operators should watch two follow-on moves in the next six to nine months. First, whether consulting firms — Bain, McKinsey, Accenture — launch dedicated effectiveness-function buildout practices, essentially productizing what they already do ad hoc. That would confirm enterprise demand and create a hiring category. Second, whether boards begin requiring effectiveness leadership as a condition of CMO appointments, the way CFO hires now assume audit-committee fluency. If neither happens, the 47% becomes the ceiling.

The study arrives as media inflation continues and platform attribution becomes less reliable, not more. Brands that formalized effectiveness three years ago now have clean time-series data and muscle memory for hard conversations. Brands without it are guessing, which works until it does not.