Gamines with long hair vs short hair
Long hair frames the face and softens it to a more rounded shape, obscuring the lines of the jaw. It can also obfuscate the shoulder/neck area. Having 'big' or ruffled hair can also make your body look more petite in comparison.
While, the shorter you go, the boxier the lines will be. It's very difficult for anyone to pull off a super-short haircut because it lacks fluidity and shape and is rarely flattering. On the flipside, if you have a nice jawline, neck and shoulders, a short haircut can be much more striking than long hair.
I'll say that bob-length (usually the shortest a female idol ever goes) creates the same rounded shape in the face as long hair. One thing is a bob won't drag you down physically/make you look as short as longer hair would.
Jeongyeon is one of the few female idols who had actually short hair. You can see the difference in the shape and the effect it has.
Longer hair detracts from your jaw. Bangs have a similar effect. They add volume to the top of your head (forehead) which in turn makes your chin seem smaller.
When it comes to balancing, yin-dominant people look better with short hair and vice versa for yang people. Short hair suits smaller, more compact people while long hair emphasizes yang vertical. For Gamines, short hair is explicitly recommended.
I think Nayeon looks best with a not too long, not too short haircut. Around shoulder-length. Any shorter, I don't think it emphasizes her beauty as much. Her long hair can be good, but too long, and it drags her down.
From T-ARA, for the youngins. Boram is a good example of a gamine who adheres to recommendations. Bangs make her hair seem shorter and breaks up her face shape, and even when she has longer hair, it's usually tied back so it isn't too heavy.
This may just be me, but Soyeon with long hair... I feel like something's missing! With her hair shorter, it looks so much livelier and suits her perfectly. I don't always love the way she's styled with a bob, but I think she looks most jaw-dropping with short hair.
Choa, again, shows how gamines can transform with a short haircut. With her short hair, she appears youthful, almost fairy-like and more distinctive. While, the longer hair can get in the way and just muddies her face, neck, etc and honestly looks a bit childish.
Like Choa, Minzy also benefits from shorter hair. It's a huge difference. She seems more 'lifted' and striking.
Chaewon is interesting--like Choa, part of her identity (in Lesserafim at least) is having short hair, which adds to her doll-like features. She wears it nicely, but she also looks great with long hair. I wonder if it may be fatigue from seeing her with short hair a lot of the time, so her long hair seems more striking. Either way, she looks good in both.
You might say some (or all) of these female idols look better with long hair... some of that may be societal norms of women having long hair, but no matter what, gamines are recommended short hair not because they all look much prettier with it... but gamine outfit recommendations simply don't work with long hair. The visual staccato effect of broken up lines is affected with long hair in the way.
