|---loop 1---|
     |---loop 2---|
          |---loop 3---|
               |---loop 4---|
                    |---loop 5---|
[/code:3an33utc]
But the problem is that I need the first loop has been executed completely for the next iteration is executed correctly. As the second loop may start is starting parallel to the first loop, the second loop the result will be incorrect as the result of the first loop has not been fully calculated, and therefore, is also wrong.

I need some loop like (sequentially)
[code:3an33utc]
|---loop 1---||---loop 2---||---loop 3---||---loop 4---||---loop 5---|
[/code:3an33utc]
one after one;

But the problem is that I need the first loop has been executed completely for the next iteration is executed correctly. As the second loop may start is starting parallel to the first loop, the second loop the result will be incorrect as the result of the first loop has not been fully calculated, and therefore, is also wrong. 

Added two cases where only changed the runtime of these two loops with Wait 1.0. 
Suppose that is 1.0 Wait time processing and some other function that may last varying time. 

If the loop were sequential, the result would always be correct regardless of the time that each block of the loop had. 
As these blocks of shares of loops are executed in parallel, it can not guarantee determinism, ie, the result will always be correct for a given system configuration.

=D