Facets: Auto Buckets -> Inconsistency?

I noticed something seemingly inconsistent in this lecture:

Chapter 4: Core Aggregation - Multidimensional Grouping
Facets: Auto Buckets

Or maybe, it is just one detail that I do not know about?

At clock timing 3:09 we see that numbers from 1 to 1000 all inclusive, are inserted in a collection. But we also see later at timing 3:32 that, all 5 buckets containing exactly 200 elements, the last maximum is 1000. Shouldn’t it be 1001?

Looking at the discussion posts, it seems I am not the only one to have noticed it. See:
this other post.