Item 2 passes w/o any operations being performed.

[switheyw]

The first function below, does not make any calls to operation(), but is still seen as correct.
This is so even though only dashes were logged to console.

function repeat(operation, num) {
   if ( num == 0 )
      return
   repeat(operation, num - 1);
}

The solution as supplied:

function repeat(operation, num) {
      if (num <= 0) return
      operation()
      return repeat(operation, --num)
    }