Why good leaders make bad decisions

Leaders rely on past experience whatever they learned by the past experience , but is actually sometimes dangerous. One of the most well known [examples] is Dick Fuld at Lehman. He saved Lehman in the aftermath of the LTCM crisis in the late '90s. Fast forward 10 years or so and he also, I believe, thought he would do it again. But the experience he was relying on was not the same as this massive housing-driven collapse. It's much more complex, much more complicated.
It is one of the most important responsibility of the leader to get right decision at right time and place. As I defined leaders mostly rely on their past experience for instance, a CEO of ABC company is willing to invest money anywhere for the contingencies. Now he has to take decision that where he should invest the money so he will go to his past experience and will make investment but it is not necessary that where he invested money earlier by which he earn a huge profit. There is no surety he will make profit again by investment at the same place. He will have to analyse the current market then will make investment if he doesn’t do so, he might be fallen in trouble.