Bernd probably knows that search engine crawlers go around indexing websites, following links to one site from another.
But does Bernd know, that Google crawlers can find a webpage without it being actually linked on another website, I'm guessing from other kind of linking like in chat (on an android) or maybe from searching the website name in their service. BUT. They won't include it among their search hits, until the "owner" of the website explicitly tells them, that he has this google account, and he has that website?