A) The set-up: Character introductions. The movie begins with an amateurish method of introducing the characters that is literally one person listing their names and features followed by a flashback scene for each. Dumbest exposition structure ever.
B) The Mission: Load everybody up in a helicopter, give them weapons, send them along their way. This plays out as an extension of A where each person gets a montage playing with their toys of choice.
C) Switcheroo: Plot twist that changes the mission objective. Unfortunately, the movie fails to adequately set up this core plot point because the director spent so much time showing off weapons and Margot Robbie's arse, he forgot to have a character explain the mission in any memorable way. When the twist in the mission objective is "revealed" midway into the siege, it's more confusing than revelation. At this point, no sane person is looking for coherence in the film anyway, so it hardly matters.The directorial style can best be summed up as 'just keep everyone shooting guns, no one will notice the incoherence'.