Why are all those bringing up dreadful examples of CN's gone...

Why are all those bringing up dreadful examples of CN's gone wrong not focussing on what part to play the investment opportunities themselves within those deals where? I am not sure if anyone of those companies would have been a success with or without the CN financing or if alternate funding would have changed their fate? Did they have the same latent explosive potential as the opportunity right in front of us? I don't know but have a feeling that this question is a far more important one to be asking.