Polygon Divider QGIS Plugin creates less equal parts (polygons) than asked

I’ve installed QGIS 3.16 for Windows. I digitised a polygon layer (limits of a city) and used the Polygon divider plugin to divide it in 10 equal parts (polygons).

However, as a result, it created only 9 equally divided polygons. (When I tested it, asking for 9 equal parts, it did create 9 polygons. But when I tried for an 8 equal parts division, it again gave 7 polygons).

Could please someone enlighten me?