Why the default value has to be set outside of the if

[Metry]

I’m trying to make a function that checks whether any element of an array satisfies its conditions. The below code doesn’t work, and it only returns undefined.

function findElement(arr, func) {
  for (let i = 0; i < arr.length; i++) {
    if (func(arr[i]) == true) {
      return arr[i];
    } else{
      return undefined;
    }
  }
   
}

The code below this works properly.

function findElement(arr, func) {
  for (let i = 0; i < arr.length; i++) {
    if (func(arr[i]) == true) {
      return arr[i];
    }
  }
    return undefined;
}

Why can I not put else {return undefined}? I don’t understand why the first code doesn’t work and the second does.

[sanity]

Assume that arr has two elements, for first one func will return false, for second true. Consider what is returned by each of these functions in such case - try going step-by-step through the function.