Returns in a recursive function

I am trying to understand how to use recursion in C, and I can't get how return works in it.

Please consider the following code:

int     recur(int i)
{
    printf("recur: i = %d\n", i);
    if (i < 3)
    {
        recur(i + 1);
        return 10;
    }
    else if (i < 5)
        recur(i + 1);
    return i;
}

int     main(void)
{
    int     i = 0;
    i = recur(i);
    printf("i = %d\n", i);
    return 0;
}

The output is:

recur: i = 0
recur: i = 1
recur: i = 2
recur: i = 3
recur: i = 4
recur: i = 5
i = 10

What does the last return, return i, do? Does this code even make sense?