doesn't crap go wrong as you get all cocky about how it's all going according to plan? doesn't matter how much you planned, how many unlikely eventualities you account for, you think like that and you lose badly. I mean f***ing Aizen couldn't even win after he went and bragged about everything being part of his grand plan, seriously, the dude literally planned the path for ascension to a state of what would have been essentially godhood CENTURIES (if not millennia) in advance, actually had everything go absolutely perfect according to plan, then he went and blabbed about it...and failed at the last moment cause he got the shit beat out of him by an angst-y teenager
you simply do NOT think things like that unless you actually want it all to go nuclear in your face