... the ball is small enough to fit between two pins ...

Skipping over the logic-chopping (or syntax-chopping), you are quite correct, Faldage. It won't go between pins when all 10 are standing, but it often goes between two (or more) pins without hitting any when some have been already knocked down. Of course this is true in tenpins as well, especially if you are faced with "lighthouses" -- the 7-10 split -- but you rarely see the tenpin ball miss everything with any split less disastrous. It happens frequently in duckpins. And in duckpins, the 7-10 split is even more difficult to make.