Two people can do the exact same exercise, the same weight, the same reps, and get completely different results. The variable that explains this is not genetics or effort level. It is the mind-muscle connection: the degree to which you are consciously directing attention and neural drive to the muscle you are trying to train.
The science behind it
Muscle activation is regulated by the nervous system. When you focus on a specific muscle during an exercise, you increase the recruitment of motor units in that muscle. Research has shown that simply thinking about a muscle during an exercise (internal focus of attention) increases its activation by as much as 22 to 60 percent compared to just thinking about completing the movement (external focus of attention). This is not a motivation concept. It is neuroscience.
This effect is particularly significant for muscles that tend to be neurologically inhibited, meaning muscles your brain has learned to underuse. The glutes are the most common example: many people do dozens of hip thrusts and barely feel their glutes because their brain defaults to recruiting the hamstrings and lower back instead. The exercise is not wrong. The neural drive is just absent.
How to develop it
Start by practising muscle isolation with bodyweight before adding load. Feel your glute activate in a simple glute bridge before you load a barbell hip thrust. Feel your lats engage when you pull your shoulder blade down before you attempt a row. These pre-activation drills create the neural map you need to maintain focus under heavier loads.
Slow your reps down. A three-second lowering phase forces you to stay connected to the working muscle throughout the full range of motion. It also removes momentum, which is the enemy of mind-muscle connection. If the weight is moving on its own rather than being controlled by you, you have lost the connection.
Cues that work
For glutes: Imagine you are trying to crack a walnut between your glutes at the top of each rep. Sounds strange, works every time.
For lats: Think about pulling your elbows toward your back pockets rather than pulling with your hands.
For core: Imagine bracing as if you are about to take a punch to the stomach, not just sucking your belly button in.
For chest: Think about squeezing your hands together while pressing, even though your hands are not touching.
Quality reps with genuine muscle connection will always produce more results than high volume done mindlessly. Train fewer reps better before you train more reps worse.