If you have the compiled assembly obviously you can say exactly what will happen. I agree with your meaning somewhat though that more often than not many people have no clue, especially with large systems. Its not as bad as your statement though..
The issue is not so much how this code is translated from higher abstraction level to lower abstraction level... the issue is, that this code represents a simple chaotic function (the logistic map). As such, for a simple few lines of code the behaviour is very complex and virtually impossible to predict; for certain values of the controlling number it will (1) halt relatively quickly, (2) never halt, or (3) halt after a very long time... but good luck in distinguishing between cases 2 and 3!