Pinkie’s hair deflation definitely doesn’t come from anything minor. Unlike some others, I actually really, really like that her hair doesn’t deflate in the last example - it just puts power behind the others. Pinkie Pie only ends up straight haired and broken souled when it comes to a disturbance at the very core of her being. Pinkie’s a pony that needs direction, and she is very loyal to the path she’s going down. Total deviations from it leave her very, very lost.

I know a lot of people just look at her as the stupid random pony who’s there to make jokes, but its more like she’s so determined to bring joy in to the life of others! She really does live for everyone else. She’s said it herself, what makes life worth living is putting a smile on someone’s face. Without that, Pinkie Pie doesn’t value herself at all, as much as she wants to mean something to others so she can give them comfort, laughter and happiness.

Making her hair deflate at smaller opportunities just detracts from the real (and unique!) gesture, which is pretty damn annoying.

“An Examination Into Fictional Equines Physiological Reactions to Existential Crises & Psychological Stress” by Twilight Sparkle.