Just to list a few examples of someone who has POOR hip mobility:
It is indeed very common find people of all ages and of both sexes to have poor hip mobility. There is not one particular cause, but rather a plethora of contributing factors: prolonged sitting, prior injury, leg length inequality, lack of stretching, lack of mobilizing the hip and most commonly - a general lack of awareness of how important one's hip mobility is. Yes, excuses literally. The hip joint is designed to be extremely mobile and at the same time very strong and sturdy to weight-bear. It is a ball and socket joint that allows a wide range of articulation in multiple planes. However, the above causes often contribute to limit one's true potentials of fully utilizing the hip joint, thus further hindering one's total body mechanics.
So what restricts motion in the hip joint?