Recursion - Return 1 versus Return Variable

Question

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace SoloLearn
{
class Program
{
static int Fact(int num) {
if (num == 1) {
return 1;
}
return num * Fact(num - 1);
}
static void Main(string[] args)
{
Console.WriteLine(Fact(6));
}
}
}

I understand that return 1; is the exit for the recursion.

static int Fact(int num) {
if (num == 1) {
return 1;

I don't understand how using 1 returns the value of num to the caller.

Wouldn't it make more sense to return num explicitly like below?

static int Fact(int num) {
if (num == 1) {
return num;

Answer 1

Since the if statement checks to see if num equals 1 then returning num or returning 1 are equivalent, it doesn't matter which one you use.

There may possibly be some efficiencies gained by using a constant (1) rather than a variable (num) but suspect it wouldn't be noticeable.

Answer 2

Another advantage over 1 is that if for whatever reasons you need to change the variable's name you'd only need to change it once. "Syntax efficiency"