RE: Top five reasons organizations fail at project management
Incompetency or plain old lazyness are much easier to hide and tons of excuses for not delivering can be provided in organization without formal project management methodology.
Harold Kerzner wrote: "Project management is the art of creating the illusion that any outcome is the result of a series of predetermined, deliberate acts, when, in fact, it was dumb luck".
I tend to agree with that more and more