Why do advanced users move from Power Query to Python for Excel automation?

I've noticed that many data professionals recommend switching to Python (especially pandas) instead of relying only on Power Query when Excel workflows become more "serious" or complex.

From an Excel user's perspective, Power Query already handles cleaning, transformations, merging tables, and automation pretty well, so I'm trying to understand where Python actually becomes the better tool?

I am interested in real-world experiences and decision criteria especially from those who used both or one of them.