Then think of this. There is a glass of water. 10/10ths of it would make it full. 0.99/10ths of it would make it almost completely full, but 0.01 of it would not be full.

That 0.01 can apply to any number of 0.99s. By this I mean that 0.9999 has 0.0001 empty, etc., so on and so forth.
That changes when you make an infinite series of nines. There is no such thing as an infinite series of zeros with a 1 at the end.