When it came to be used by light infanteers in the open, using light infantry tactics, the musket lost most of these short-comings and became an accurate and effective weapon. Light infanteers were taught a lot of the same tactics that riflemen were taught, using cover, picking targets etc. In 1812 you were considered a very good shot if you could hit a man sized target at 200 yards. At any range over this the rifle was merely a harassing weapon, fired at targets of opportunity to keep a man's head down. Yes, there are instances of men hitting targets at greater distances but these are the times when this type of thing is noted and written down.
Nobody ever notes the amount of missed shots required to get the one that counts.
At this our particular stage in history the rifle as an effective weapon was still in its infancy. Before then it is just too slow to be effective. A very good indication of this is in limited amount of rifle troops that Britain has. A lot of people considered them to be novelties at best. At around one hundred yards I can hit that same snowman 3 out of 4 times after one or two ranging shots.