If you truly knew what you were doing when you started, then everything would work the first time you tried it. Since that's not the case, you're clearly making

If you truly knew what you were doing when you started, then everything would work the first time you tried it. Since that's not the case, you're clearly making mistakes, so why wait until running it to find mistakes when you could find them before even running the program? Think of it this way: you only ran it 10 times, are you sure you found all the bugs? What about 11 times? Are you sure you found all the problems? Numerically speaking, if the first 9 attempts didn't work, then 90% of the time you ran it after coding, it was still broken. The fact that the program was broken a majority of the time you developed it should make you skeptical if it's even "correct' after you've determined it to be "finished". I understand you picked random examples, but this is still relevant. It seems to me like you're arguing a common argument about picking tools which is "I've always done it this way, and it works for me, so why look for anything better?"