What I also love about these album exchanges is the showcasing of the synergy within the team. The energy is something you can't build regardless the length of time. What makes BTS successful is their ability to complement one another. They are truly the missing piece in each other's puzzles.

It's also a sign of a 'dreamteam'. Can apply to successful casts (Friends, Seinfeld, Big Bang Theory I recalled on the spot), bands (Queen), etc - take one team member out and magic transforms into a memory. Often nostalgic, sometimes not even poor, but a memory.