My Toilet is Dirty with Poo

I was cleaning my toilet today when I realized something odd.

Girls toilets are usually cleaner then boys toilets. This can probably be attributed to the fact that, stereotypically, girls clean more. Now this just doesn't make sense to me. Why you may ask? Well, when I went to clean my toilet today I lifted up the toilet seat and discovered that it was in fact very dirty inside. I had not previously noticed this, as I tend not to lift up the toilet seat. While it was down it seemed quite clean still.

Now, since guys pee standing up then they would obviously notice that the toilet is dirty when they lift the seat up. So in theory shouldn't guys clean their toilet more often because of this? o_O