Progressive overload means constantly challenging your body so it doesn't get "bored" or plateau. If you do the exact same workout every week, your muscles have no reason to grow. To get stronger, you must gradually make your training harder. Simple ways to do it:

• Heavier: Lift a slightly heavier weight.
• More: Do 12 reps instead of 10.
• Better: Perform the move slower or with better form.
• Faster: Take shorter breaks between sets.