Four litter boxes for four cats, cleaned twice daily. Why you still poop on floor, kitty?!

Picture of litter boxes. Cat poop warning!

Anyone know how to combat this? We've tried a bunch of different ideas but nothing has worked! I think it's the older one doing it. If we have the litter boxes in the corner, they poop in the middle of the floor. If I put the litter boxes in a square formation to block off the corner, they hop over the litter boxes to poop in the corner. What am I doing wrong? Do I need even more litter boxes?

For picture context: The two trashcans are what I scoop the poop into, and I take those out once or twice a week. The litter boxes were cleaned about 9-10 hours prior to taking this picture. This was just after getting back home from work.