Part of the reason for this discrepency is muscle memory.
This was first noticed in athletes who suffered injuries to joints. If they were not encouraged to begin using the joint again as soon as possible they were more prone to suffer further injuries to that joint. Studies showed that our muscles learn specific little routines to cope with the high speed demands we make of them. The human brain alone cannot do all the parrallel processessing necessary to orchestrate every little motion when when time is of the essense. When injured, our muscles can quickly forget these routines and when our brains try to draw on them again in their absense disaster can strike.
You might find the same is true for other joints on your body, that differing sides have differing abilities in this reguard. This can be influenced by the amount of billateral symmetry you possess, among other factors.