Did you know that, according to the software guru Steve McConnell, developers make between 10 and 50 errors (=bug) per 1,000 lines of code (LOC) at the first attempt? The good news is that with various QA measures this can be reduced to about 0.5 bugs per 1,000 lines. What does this mean for the software application? Note: The current Windows operating system has about 50 million lines, Facebook about 60 million, all products of Google together about 2 billion lines of programming.