One of the main flaws I see in most people's deadlift occurs when they start to initiate the descent back to the ground. After lockout, I often see people trying to "squat" the bar back down to the floor. That is, they'll break with their knees (essentially performing an anterior weight shift), which results in the bar having to travel around the knees, resembling more of a squat than a deadlift.
Bad Deadlift Descent
Instead, I like to use the simple cue "sit back" when trying to teach the hip hinge pattern. More specifically, I tell my athletes: "I want you to imagine I'm standing behind you with a rope around your waist. When you descend, pretend I'm pulling your hips back with the rope."
Good Deadlift Descent
Effectively, I'm teaching them to incorporate a pattern that resembles more of a hip hinge/posterior weight shift. By doing so, we place a greater emphasis on the hamstrings and glutes, which is the point of the deadlift in the first place.
If you're not used to it, it will definitely take some practice. But if this sounds like you, it's definitely going to be an ego check, and I highly suggest taking some weight off the bar until you're able to groove that proper hip hinge technique. It will make all the difference in the world.