It's common sense, everybody knows that you cannot learn if you don't admit and own your mistakes. It's very basic actually. Nobody learns when they don't even acknowledge their own mistakes.
But if you simply acknowledging your own mistake and carry on as before, your still in danger of repeating the same mistake again. Put those lessons into practice and careful with your choices, read again and again the rules and follow it by heart.
Yes, you can learn faster but not all people has the ability to listen and remember the advices from someone who committed mistakes. Some has been taking it for granted. What's the purpose of learning faster from others mistakes if you don't even know how to admit your own mistakes and learn from them? We need experience to understand. You can't always rely on others because they are not always there for you when you need advices. You need to learn to stand up on your own feet without anyone's help because they cannot help you all the time and i also wanted to add that there is nothing wrong in relying on yourself.
Yes, I agree that you can learn the most from your own mistakes, it can give you the required experience and the intense feeling of regret that you will never ever do it again. But is it much wiser by learning from the others than suffer the consequences of committing those mistakes? Why wait for yourself to stumble than watching the other so you can make careful choices?