The posterior chain is the most common weak point for lifters. For one, we spend hours sitting on our asses, placing occlusive pressures over the gluteal and hamstring groups, along with functionally shortening the anterior structures of the legs, hips, and pelvis.
This is the exact reason why we need to "prime" the hams and glutes with certain exercises before we do the big lifts. Posterior chain primers also help to further lubricate the hip and knee joints while activating stabilizing musculatures that play a key role in clean and crisp compound movements like the squat and hip hinge.
Since the hams and glutes don't get enough credit for their roll in stabilization of the hips, pelvis, and knees, placing a "first things first" mentality into your leg day can be a game changer. The go-to movements for lower body primers are the hamstring curl on an exercise ball and the hip thrust.
Hamstring Curl on Ball
Do these exercises with a slow tempo and higher reps. It's not necessarily the exact exercise that's important but rather the intention you execute these movements with. Tap into your mind-muscle connection and work these tissues hard with some volume and minimal rest periods to get your lower body training going for the day.