High squat mobility, poor control. This is more common in females, but also in males who've played sports that demand extra mobility as a kid, or who have a lot of congenital joint laxity.
For these people, they need to focus on trying to control the movement more, which means slowing down and thinking about positioning and trying not to bounce through the movement.
related posts
Bad Back, Big Muscles
Nagging back pain is no excuse to get fat and weak. Here's how to keep training hard while your back heals up.
Tip: The Cure for Functional Weak Links
Every lifter needs more rotational work in his programming. Try this exercise.
Squat Like a Champion
Squats aren't for everyone, at least not right away. Here's how to systematically work your way up to squatting like a champion.
The One Arm Push-Up
The easy-peasy push-up gets a heck of a lot more challenging once you remove a hand from the equation. Here are some tips on mastering this old-school feat of strength.