What are the exercises where it's most important to have your shoulder blades retracted?

[GolovKing]

I'm guessing it's the higher up in weight you go but also once you've sustained shoulder injuries it becomes more important? But what exercises specifically are the ones where you want to do it, because I see a lot of confusion online? Some say unretracting your shoulders at the very end and getting that extra little movement is also beneficial. Also isn't having your shoulders always retracted kind of unnatural for most sports?