I have definitely done my share of learning the hard way. As much as we want to share our hard learned knowledge, and help others avoid making the same mistakes that we did, it just doesn't seem to work that way. We all seem pretty determined to make the same mistakes for ourselves.
On that note, as I get older, I like to think that, while I am still making mistakes and learning things the hard way, I like to believe that in my older age there are a lot of things that I have gotten much wiser about, and make much fewer the real stupid mistakes.
So when I see people my age and older that are still making the mistakes that we all should have learned very early in life, I often wonder how these people failed to learn such an easy lesson. It is evident that they have made the same mistake many times before, and had the opportunity to learn from it.