Ah, my mistake, you are correct. That being said, the example has another flaw: it is based on completing an infinite number of finite time tasks in finite time

Ah, my mistake, you are correct. That being said, the example has another flaw: it is based on completing an infinite number of finite time tasks in finite time. That is to say, adding and removing an infinite number of balls will take an infinite amount of time, but we're only given an hour to do it in. Note that this is different from Zeno's paradox, wherein the two racers each have to move an infinite number of ever decreasing distances in ever decreasing time (as opposed to constant amounts of time).