Humans are prisoners of time, but the gods are outside time.
This is the insight that Aeschylus had. It had taken that long for the full implications of immortality to sink in. In Homer, they still tend to act like children rather than gods. For Agamemnon, a cut on the hand is agonising, and he withdraws from the fighting, leaving the way eventually for Hector to dominate the plain. Apollo is vindictive.