Ask HN: Why does $50M buy just 10% productivity for Enterprises?

I read a report done by KPMG where they mentioned AI spent is above $50m for almost all tech companies above billion dollars and still productivity gain is 10%.

What opportunities does it open?

Source: https://www.fortuneindia.com/amp/story/technology/ai-adoption-is-near-universal-but-only-10-of-tech-firms-achieve-roi-at-scale-kpmg/154914