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# Off-the-shelf MMM tools can diverge wildly from custom models, op-ed warns
- URL: https://www.medianexis.com/off-the-shelf-mmm-tools-can-diverge-wildly-from-custom-models-op-ed-warns/
- Published: 2026-10-19T16:53:47.000Z
- Updated: 2026-10-19T16:53:47.000Z
- Description: AdExchanger is reporting that an off-the-shelf marketing mix model estimated 10 paid channels drove roughly 75% of new-customer volume, while a custom build using identical data found under 1% incremental contribution.
- Author: The Signals Desk
- Tags: Measurement, AdExchanger Guest, Off-the-shelf MMM tools can diverge wildly from custom models, op-ed warns

**Why it matters.** Marketers who rely on a single automated MMM run risk misallocating budgets unless they stress-test results against custom modeling and experiments.

*Signal from* [*adexchanger.com*](https://adexchanger.com/?ref=medianexis.com) *·* [*AdExchanger Guest*](https://www.medianexis.com/tag/by-adexchanger-guest/) *·* [*read the original*](https://www.adexchanger.com/data-driven-thinking/mmm-is-getting-smarter-it-still-cant-do-the-whole-job-alone/?ref=medianexis.com)*.*