Iirc historically the day was first split into 12 parts with sundials, and only later was the night also split into 12 parts. Maybe thats where the 2x12 comes f

Iirc historically the day was first split into 12 parts with sundials, and only later was the night also split into 12 parts. Maybe thats where the 2x12 comes from. I guess another benefit is that it's simply less cluttered with 12 divisions.