Dancing with the Stars

I love this show. I love to dance but can't so I guess I live out my wishes through them. I am impressed by some how quickly they pick up the moves, then there are others who like me who can't get it together at all. Sometimes I am sad to see them go home because they provide an element of laughter to the show. What I can't figure out though is how 3 judges, looking at the same dance can come up with different scores so far apart. last night for example where, if I remember correctly, Len went to a 7 the other two were 9 and 10. How is that really possible?