Yeah, not sure if it's a mental roadblock but it's painful to incrementally improve something especially if you've learned of better ways (which happens a frequently as a jr) as you end up fighting with your own idiot self.

Bad code is laid down at day 1 and everything past that is just worsening it even if it appears to be a positive refactor. Torch the canvas and embrace the cycle.

Not that it has to be preplanned, per se, as the absence of planning before day 0 still becomes plans on the day IME.