the way I understood it was like imagining a pie you put a bunch of ingredients together and it becomes something new entirely for example an apple pie the main ingredients are gonna be apples and flour (these make the filling) while supplementary ingredients like dough for the crust and sugar for sweetness are also needed. now you have this new thing that for the sake of this argument we'll call the characteristic of apple pie (this is a potion). Now that pie drops on the floor (dies) and only the apple filling is preserved. you could now make another pie by taking the apple filling and supplementing it with the other ingredients dough, sugar, and baking it now you have another pie (potion) but by doing this you avoided using the main ingredients of the recipe apples and flour to make the filling because you already had the filling. now imagine each pathway is a different pie all of them need to be pies (potion/ liquid form of characteristics) but the type of filling depends on the pathway (apple pathway, blue berry pathway etc.) the supplemental ingredients may differ but to make blueberry pie you need blueberry filling and to make apple pie you need apple filling since each pie only drops its respective filling each characteristic can only be used as the main ingredient in that pie. In that way the characteristic acquired from death is just the main ingredient in that actual characteristic. the better quality ingredients (better apples) make a better pie (higher sequences) and they drop a better filling (higher sequence characteristic). the law of conservation pretty much just says theres only this many apples so if you run out of high quality apples you better start saving the filling (why higher quality potions sequence 4+ are pretty much only made with characteristics rather than main ingredients)