"I want my code to run fast, so I pick the fastest language runtime for my code", says the dev who does not know the ways of the tao.

Behold, their JS code:

// remove items equal to "item" in array "arr"
function removeItem(arr, item) {
   let idx = arr.indexOf(item);
   if (idx < 0) return arr;
   let newArr = [];
   for (let i = 0; i < arr.length; i++) {
      if (i !== idx) newArr.push(arr[i]);
   }
   // isn't recursion great?
   return removeItem(newArr, item);
}

(this example isn't realistic because This Type Of Guy typically uses TypeScript with any all over, but I was too lazy to do that)