We recommend all creators to turn on personalized ads in order to maximize the revenue they earn on YouTube.
Google can personalize ads so they're more useful to you on Google services such as Search or YouTube, and on websites / apps that partner with Google to show ads.
Turn on personalized ads
Go to your Google Account.
On the left navigation panel, click Data & personalization.
On the Ad personalization panel, click Go to ad settings.
Click the switch next to Ad personalization is OFF.
Edit your info or interests
Under "How your ads are personalized," select your personal info or interests.
To update your info, select Update. Follow the steps on the screen.
To turn off an interest, select Turn off. Confirm by selecting Turn off.
To bring back an interest, select What you've turned off. Choose an interest and select Turn back on.