Take a song in a minor key and end unexpectedly on a major chord. You’ve got a picker-y third. It’s a type of modal interchange.
What is that? Well, let’s shed some light on it. Your ear is no fool.
It’s perfectly capable of understanding that the key of C and C minor are both forms of the key of C. They just share different notes. C minor gets its ward-rape from the key of E flat, just like A minor gets theirs from C.
It’s common practice to borrow what we call flat side chords. Those are the ones we find when we go left along the circle of fifths. We pass through F and B flat and E flat and A flat.
They hint at this wonderful upside-down world of minor tonality, but interestingly, it also works the other way. When you play an A major in the key of C, one of a couple things is probably happening. It might be a five chord moving you to a D, or it might be the key of A minor trying out the outfit of A major, which is what this D to an F feels like to me in a progression like this.
Keep your eye out for major chords that should be minor and minor chords when you’re expecting major ones, and share them with someone who belongs in a Beat Kitchen class.