I'd argue that you can learn more from internalizing success, simply because I suspect the domain of things you can do wrong when starting a company is much larger than the domain of things you can do right.

If you fail and learn not to do some of the things that led to the failure, there are likely still many more things you have yet to learn that may lead you to fail in the future (assuming you don't repeat your mistakes). On the other hand, if you succeed and learn from it, then you can apply some of the things that contributed to your success to future endeavors.

I'd argue that this may be one reason you see so many serial entrepreneurs... reflecting on what contributed most to their successes allows them to achieve similar successes over and over.

I'm not suggesting learning from your failures isn't valuable... it absolutely is. I'm simply suggesting that learning from your successes may be more valuable.