The foundation of most pieces of advanced engineering lay in their material composition. Powerful exotics with myriad effects not accomplishable by mundane metals such as titanium and palladium lent their abilities to achieve powerful effects such as all-encompassing stealth or reaching an unheard of amount of energy density!
In order to simplify the application of mature technology systems, they each listed out recipes of must-have exotics. Without a set number of these exotics in a set combination, the technology couldn't be substantialized.
It was like how someone wouldn't be able to bake an apple pie without getting their hands on an apple.
Of course, one didn't need to follow the recipe strictly if they were proficient bakers. If they wanted to, they could replace the apple component of the pie with pears or berries. As long as the user of the technology knew what they were doing, they could perform endless tweaks on the recipe.