battery capacity

i just wanna ask, when i charge my macbookpro (brandnew, just bought it this january 2013) the led color in the magsafe is orange and when its full it changes to green, that is what i know, but the thing is it changes to green so i unplug the magsafe and the battery meter says 98% and its already charged and turned green. is there something wrong with it or that's it, it doesnt go until 100%?