Consider MOBILITY before load
Your ability to complete an exercise correctly and through its full range of motion will depend on your mobility and strength. Range of motion refers to the ability of your muscles to move your joints, an example of this is straightening and bending your knee. If you are not very active, spend a long time sitting or are returning from injury, the range of motion and mobility of your joints may be affected. If it is affected, your ability to complete some exercises correctly may be hindered.
Lets take a look at a squat. The squat requires adequate mobility at the ankle, knee and hip joint to be completed correctly. If you have not exercised in a while, or have been sedentary for some time, you may find your joints feel stiff and rigid. When you attempt to complete the squat, you might find it challenging to get low to the floor, feel tightness through your hips or ankles, while finding it hard to maintain balance.
Restoring your range of motion prior to doing this exercise can help and will ensure you are able to handle heavier loads safely. In reference to the above example, foam rolling the calves and holding a deep squat for an extended period while using a small weight as a counterbalance can begin opening the hip and ankle joints that will be used during the exercise. Taking the time to restore your joints range of motion by doing exercises focused on restoring your mobility can be beneficial, ensuring you do the exercise correctly and stay injury free.