Resistance is the game
Think about this. The name of the game with resistance training is resistance. That sounds redundant but think about it. What is resistance? it emerges from two forces the force of my muscle against the force of gravity when those two force collide than resistance emerges. When resistance emerges than fatigue is created. Fatigued in the muscle is the stimulus for change.
Think about how many times we go to the gym thinking the magic is in the weight or the reps or some exercise and we never experience the resistance necessary to create change in the muscle. Or we only experience it when we get to the last two reps or the last set we do. That is a inefficient way to train and increases the amount of time we spend in the gym. Find the resistance or have some one help you to find it than stay on it until you can no longer move the muscle that equals results.