I’m not sure what you want to do. The events are checking the timer’s elapsed value for 10 million seconds. Without reaching the number and using a restart timer action, it’s adding a wait every frame. After 3 seconds the first wait will expire and add an object followed by all of the other built up waits on the following frames. After the first 3 seconds, it will then start triggering the other wait but the delete action will only delete the just created object because it will be the only one currently picked.
If you just want a set quantity of the object in the scene at a time then you’d be better off moving the leaf instead of adding and deleting it.
This would create 10 randomly placed objects and then move a random one every 3 seconds.