An advertising executive takes over a Google Search ads campaign. On his Google Ads Recommendations page he notes that the campaign’s optimization score is 40%. What does this score indicate?

The campaign could be improved by 60% if the listed recommendations are followed

If he notes that the campaign’s optimization score is 40%. It means that the campaign could be improved by 60% if the listed recommendations are followed.

Optimization score is an estimate of how well your Google Ads account is set to perform. Optimization score runs from 0% to 100%, with 100% meaning that your account can perform at its full potential.

Learn more here: https://support.google.com/google-ads/answer/9061546