Maturity has a lot to do with it. It's pretty normal for a mature hen to not allow an immature rooster mating priviledges. Part of that is that the mating ritual demonstrates dominance. If the rooster cannot dominate her by the force of his personality, he is out of luck.
Also, mature hens prefer a rooster that properly performs his duties. A good rooster should dance for a hen, not just try to hop on. He should find food for her and let her eat first. He should maintain peace in his flock, breaking up fights and such. He should protect a hen from the unwelcome advances of a non-dominant rooster if she asks for his assistance. He should watch out for predators. Some older roosters and a lot of immature roosters don't do this so they get no respect from the more mature hens.
On the other hand, the pullets need to reach a certain maturity before they know to submit. The females have a part in this too.
Then you have the hens and especially young pullets that will squat for anything in spurs. it doesn't matter.
I've had roosters as young as 4 months be accepted by mature hens. I had a rooster 10 months old before the older hens accepted him. The roosters and the hens mature at different rates and have different personalities.
My guess is that your rooster is still too immature to be accepted by the hens. Give him time.