UNTUCKit TV Commercial, 'Elevator'

A man wearing an UNTUCKit shirt enters an elevator with a man clothed in a normal button-up. As they wait for their floors, the latter attempts frantically to tuck in his long shirt, while the prior idly browses on his phone. How does this man pull off his look so successfully? UNTUCKit insists, "Sometimes no explanation's necessary."