Vader is a Failure in Palpatine's Eyes

"Darth Maul and Dukoo were only tools in order to catch Skywalker, so they don't necessarily count."

For the sake of argument, lets say that Maul greased both Obi Wan AND Qui Gon. It wasn't really that far off from happening if you think about the battle.

IF Maul had won, then Anakin would never have been accepted by the Jedi council, and therefore would never have been trained to become a Jedi. It doesn't matter if Anakin is MADE out of midichlorians....., without training, he ain't gonna be a Jedi. No Jedi training, No powerful apprentice, no chance for Palpatine to score a "Darth Vader."

Sure, you could argue that now Anakin is totally out of place with Obi Wan and Qui Gon being gone, and perhaps Palpatine could have somehow lured him over the dark side sooner..... But then again, I just don't think it would have happened that way.