The error was essential in the sense that it was an inevitable outcome of an essential process. Similarly you might say, "exhaling carbon dioxide is not essential for survival; what you really need is to turn food into energy." But if I was prevented from exhaling CO2, I would quickly run into problems.

Bad analogy. If I don't get rid of waste products I will die. If I don't make a mistake I will... succeed more quickly and be unrealistically lucky. That's entirely different.

To say the error is essential is a mistake. The error is inevitable, not essential.