What do you feel when you discover that your reasoning is flawed? when you find your recurring mistakes? when you find that you have been doing something wrong for quite a long time?

Many people feel bad. For example, here is a quote from a recent article on LessWrong:

By depicting the self as always flawed, and portraying the aspiring rationalist's job as seeking to find the flaws, the virtue of perfectionism is framed negatively, and is bound to result in negative reinforcement. Finding a flaw feels bad, and in many people that creates ugh fields around actually doing that search, as reported by participants at the Meetup.

But actually, when you find a serious flaw of yours, you should usually jump for joy. Here's why.

If you are an ambitious person, you have likely exhausted all the easy ways to improve your performance known to you; all the shortcuts, all the low-hanging fruits. If not, what are you waiting for? So, what's left for you is the hard ways, which require a lot of effort for relatively small improvements. Think harder, work harder, have more willpower, be more restless, et cetera. Such improvements are neither easy nor fast.

Now, suppose that you have found a serious flaw in your reasoning. 

What has happened, actually?

Firstly, you have lost nothing. All your achievements are still with you; as well as all your abilities; as well as anything else. However, one possibility is that your predictions about the future may become worse; maybe, you have just noticed that your road is leading to the abyss. But I'm talking here about noticing biases, errors and flaws that you have had for a long time, and such biases are unlikely to have irreversible forthcoming consequences. For example, if you have had a biased estimate of radioactivity effects on health and have gotten a dose -- that's an unpleasant bias to find, indeed. But most long-term biases aren't that malicious.

Secondly, now you have an opportunity to fix it. Whatever you achieved before, you achieved while being impaired by the flaw. And now, when the bias is eliminated, you can do even better. Fixing a bias might require some effort, but usually way less effort than your default hard ways of improvement. Or maybe you just got rid of some risk which could hit you in the future -- that's good too.

When I find a flaw or a recurring mistake of mine, I imagine how my life will be improved after I eliminate it. That feels good, certainly.