With incremental refresh policy, why does Power BI "SELECT TOP 1000" thousands of times?

I hadn't checked this in a long time. At a glance, right now, it seems I still see some of these queries, but they don't seem excessive anymore. With Amazon Redshift as the source. That's good -- I would call this "fixed."

I don't really understand it, but I can imagine these queries serve some purpose for Power BI. Like, maybe Power BI wants a "preview" of the data to ensure it conforms, before starting to download many more rows.

And I don't think that a small number of them (10 such queries during a refresh) would cause any noticeable issues. In my opinion, that is reasonable. (My problem was when it would execute the exact same "SELECT TOP 1000" query to Redshift dozens—or hundreds—of times. In a very short time span, for a single Power BI refresh operation. That seemed wasteful, and I was concerned it was degrading my Redshift performance.)