为什么方法会删除数组中的元素？

I'm trying to create my own .sort method as an exercise in a ruby book, using recursion, and for some reason they haven't taught me the spaceship operator yet. My code works to get the smallest value - apple - and puts it in the sorted array, and it even repeats using the recursion, and resets the array to repeat the process to add the second smallest word. The problem is for some reason it removes the smallest word -apple- and I can't figure out why. I know where I think - in the else myArray.length == 1 statement when I pop the element off the array, but why is it removing from the sortedArray too?I'm trying to create my own .sort method as an