Germany failed to see that Poland was a useful Buffer state that kept the Russian bear away. They suffered years of partial occupation much of it brutal for doing so.
Do you mean decades of Communist rule in East Germany?
And Yeah, honestly, if I was a German, I wouldn't have cared all that much about Danzig and the Polish Corridor (Alaska is separated from the US and we don't need a corridor for it!). I'd have simply wanted good relations with Poland. Instead Germany decided to gamble big and subsequently lost big, perhaps a bit like Russia is doing today, when it could have simply outright annexed the Donbass in February 2022 but instead decided to make a move on all of Ukraine because it thought that it could.