The company says:
Google is also introducing more notifications so you will be aware if a site or app is granted access to your account. There’s also a new security process that’s triggered if potentially unauthorized activity is detected. Google says it will help users:
Verify critical security settings to help ensure your account isn’t vulnerable to additional attacks and that someone can’t access it via other means, like a recovery phone number or email address.
Secure your other accounts because your Google Account might be a gateway to accounts on other services and a hijacking can leave those vulnerable as well.
Check financial activity to see if any payment methods connected to your account, like a credit card or Google Pay, were abused.
Review content and files to see if any of your Gmail or Drive data was accessed or mis-used.