Well, I somehow can’t bring myself to take apart my Bionicle sets with them beinig so nicely on display and such. Though I was forced to raid them of parts in order to build better MOCs recently … Brutaka is missing one piece, Jaller Inika two, Chirox is missing his wings, Mutran is just a feetless, maskless, wingless, handless skeleton with my revamp of him being in existence and from four of the six 2015 Toa these ball thingies they use in their shoulders were confiscated for MOCs, too.
Which leaves me partwise - with three MOCs assembled - at a, admittedly, not small box with parts, but I feel like at least 50% of those are Mata and Inika build stuff, masks, weapons and armor. I’m lacking the small pieces to build more MOCs. I even once ran out of Technic pinaxles.
So I’m pretty much forced to take apart something in order to build a new MOC and mostly those happen to be older MOCs. I often wonder what potential lies in the parts displayed in the form of sets on my shelves, but I just can’t bring myself to take my near complete collection apart on a greater scale.