Google authenticator: what does the author mean by "there is no way to get those codes back"?

I came across this article about google authenticator. I can't vouch for its accuracy one way or the other. [https://www.allthingssecured.com/reviews/security/stop-using-google-authenticator/](https://www.allthingssecured.com/reviews/security/stop-using-google-authenticator/)

The author said this:

>The Google Authenticator App doesn’t connect to your Google account and sync your codes. What this means is that unless you’ve been diligent about keeping backup codes, if your phone gets lost or stolen, and you no longer have access to Google Authenticator, you have just lost access to all of your most secure accounts. There …

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