tail recursive vs iterative algorithms

Question

I couldn't find articles describing why tail recursive functions should be preferred over iterative algorithms.

I'm not asking why tail recursive is better than simple recursive which I think is clearly explained everywhere.

So why

sum(n) = {
    def sumImpl(n, acc) = if(n <= 0) acc  else sumImpl(n - 1 , n + accumulator)
    sumImpl(n, 0)
}

is preferable to

sum = 0;
while(n--) sum += n

Answer 1

Recursion makes a program more readable, but it gives poor performance. Iterative procedures give good performance but are not that readable and may require a local variable to store an intermediate value (mutability). Using tail recursion you will get the best of both worlds and no "sum" variable is needed (immutability). This is very useful in calculating large number sums or factorials, because you will never get a stackoverflow exception as you just forward the result to the next recursive function call.

In a parallel environment immutability is very important. Try to edit your code and pass very large numbers to the function to see the difference.

Further reading here