The principle was simple. The three holes were connected. For a vigilant beast, after the first trap was triggered, its alertness and reaction would make it react quickly. Before it landed on the ground... It would be able to quickly step on the wall and leap up.
At this time, the second hole would take effect. When it jumped up, there would be a moment of relaxation. At this time, its feet would be empty. It would basically not be able to react and fall into the trap.
There would be many barbs in the trap, killing or injuring the beasts.
If it was a high-level magical beast, they might have seen through the second trap. Their outstanding reaction speed would allow them to jump up again before falling down.
However, there was still a third hole waiting for them.