It's as if some people are guided by some mysterious force, like the wind. When the wind changes directions, so do they, but no one can see the wind, so no one knows why. In contrast, the psychoanalytic approach might dissect the menacing dog image to deduce that the person's behavior resulted from fear of dogs. Somewhere between the unfathomable black box and dissecting the mind is what the writer has to reveal. Problem Action that is contradictory has to be explained.
Few viewers have blind faith that characters do strange things for rational reasons.
If Billy sees mean dogs guarding the fudge factory, but the following day to get the fudge he leaps the fence into the midst of the dogs, we're going to think there is a kink in Billy's brain. In the writer's mind there might have been a good reason for it, but to us, Billy is an idiot. Billy's action will make more sense if his friend told him that the guard dogs are trained not to bite. More often than not, it isn't absurd actions which don't get explained, it is a character decision that never becomes known to the audience. To illustrate, take a sequence in which Tim is afraid to approach Elizabeth for a date.