Considering that the height and weight of the girls are not consistent, the top band of the thigh high socks should not be too loose.
If the top band is too loose, the thigh high socks will keep sliding down. Even if the socks are very suitable when you first put them on, as you start walking or dancing, the socks will start to slide and fall on your knees, then you have to adjust their height all night.
In addition, with the increase in washing, the elasticity of the top of thigh high socks began to decrease. Their elasticity is starting to become insufficient to hug the thighs, and you may have to consider a garter belt to fit it. In order to increase the life of thigh high socks, it is best to have the thigh high socks a bit tight at the beginning. But this tightness must be elastic, not the physical limit of the sock itself.
Of course, thigh high socks should not be too tight. The top band should be very wide and can protect circulation great. The top band of some socks is just 1-2" and it will easily cut into the thigh after being stretched. All top bands below 3" may cut off the circulation. Try to stay away from such thigh high socks.