Google Earth updates its database completely every one to three years, though some sections update more frequently. Google Maps updates daily, with changes appearing on the app and website within approximately three weeks of the update being made.
Whenever Google Maps updates, a corresponding change is also made in Google Earth. There is no set update schedule for either mapping program. Changes are made as Google receives new data from the public and from satellites. It is possible to request updates on the Google Maps home page; notifications are sent to the requester when the change is made, even if it takes years. It is also possible to track changes to Google Earth through the "Google Earth Imagery Updates" button on the Google Earth home page.
The images on Google Earth are always updated as they try to provide users with the highest-resolution images possible of the different locations available. Working on the update of the images involves checking for previous images and new acquisitions, which tends to be a very slow and detailed process even for experts.