One of the most important reasons for maintaining proper form is to prevent injuries. If you are lifting a lot of weight, your body is likely to become slightly misaligned, which can place your muscles, joints and tendons in awkward positions that could potentially cause strains or tears. It is best to ease up on the weight if it means you are better able to maintain proper form.

Ensures correct muscle targeting

Since many weightlifting exercises are targeted toward specific muscle groups, a lack of good form can cause you to work out a completely different muscle or to strain the muscle you were targeting. Proper form, on the other hand, ensures optimal results in the correct muscle group.

Helps maintain proper breathing

Proper breathing is essential in resistance training exercises because it helps you generate more force and reduces the chance of heart problems or severe increases in blood pressure. When you use correct form, you will find it easier to move the air in and out of your lungs, which will also help you focus your attention on the task at hand.

Enables you to lift more weight

In order for you to lift the maximum possible weight, your muscles need to be in the ideal position to generate force. When you begin to move out of alignment, you place your muscles at unnatural angles, decreasing their functional capability. By maintain proper form, you will be able to lift a larger amount of weight, which will translate into more visible results in a shorter period of time.

Reduces unnecessary stabilizing actions

When you use bad form, a number of muscles — predominately those in your core — must work overtime to stabilize your body and try to prevent an injury from occurring. All these actions eat up available energy and significantly reduce the effectiveness of your exercises. That means more work with less results — not and ideal situation.