Glute medius is the most commonly weak lower body muscle. When strong it opens the hip joint safely. It allows for smooth and fast lateral weight transfer from right to left.

And it helps prevent the following injuries:
Labral tear
Piriformis syndrome
SI joint dysfunction
Osteoarthritis
Knee injuries
Low back pain
Herniated discs
Hip tightness
Hip flexor pain
and more

So why is glute medius strength so elusive? Not a lot of exercises that people know or see in the gym target glute medius. And, if they get glute medius involved, those exercises allow for compensation patterns. In other words, if your glute medius isn't strong and already activated before the exercise, you'll bypass it and use other muscles instead like piriformis or hip flexors. And this leads to imbalance in the joint and pain.

Check these exercises out to help you understand glute medius a little better.