Hanlon's Razor: "Never attribute to malice that which is adequately explained by stupidity."
Then there's "Heinlein's Razor" which has since been defined as variations on "Never attribute to malice that which can be adequately explained by stupidity, but don't rule out malice."
The second one is the one I prefer and - quite frankly - is far more historically correct. When you read about the personal lives of some of the most famous - or in the case of many - infamous leaders in politics, science, entertainment or business - you can't help but attribute their actions and motives to malice. And I would attribute greed as a form of malice. Greedy for money, fame, notoriety and respect - even if that respect is attained through illegitimate means.