>why would you spend the time and energy [...] perfectly though?
if you can't do it perfectly, why even bother? same answer, there is a middleground between perfect and awful and sometimes that's still worthwhile. obviously polyamory doesn't mean you'll date anyone and everyone but it can still be an enjoyable experience.

>the fact that you have to do that at all I think shows weakness and poor choice
the idea that it shows weakness is just strange but the idea that it shows "poor choice" is just wrong, things change over the course of a relationship and sometimes getting a new person to love will reinvigorate the "new love"/infatuation aspect while still maintaining the "soulmate" aspect with each other.

>grow into the person or choose a better person
this is a really random dichotomy that doesn't have to apply to anyone ever, if you two don't fit perfectly then there's no reason why you have to break up. just because you dont' bond perfeclty all the time does not mean that the relationship is invalid in any sense of the word. in fact, the VAST majority of relationships do fail within the first 6 months, and people change a hell of a lot more over the course of a few years or a decade. sometimes people in a relationship will naturally grow away from the other person, towards the other person or in a new direction entirely but it's never constant. relationship counselling is basically based entirely on the idea that "working through" a rough patch is worthwhile because there will be a time when they grow to be close again as they once were. if it's still fun to remain in the relationship, why do this? it doesnt' have to be perfect and rarely anything in the real world is.

>main issue, the root of the problem, the fact there are LARGE gaps to be filled at all
this isn't how relationship problems work at all though. gaps aren't always possible to be filled, gaps can appear over time through no fault of either party. people aren't isolated from their environmentrs and a lot of things will change the way they develop over time. there is also rarely a "main issue" or a "root of the problem" to be filled that isn't always fixable. sometimes it's a better idea to wait it out until you're ready to become close again which is kind of the whole "we need to take a break from each other" thing which is basically just getting as close to polyamory as possible without it being socially unacceptable.

>if that's the case i don't see the point in trying
that implies that you'd never do anything unless it was perfect. this is unfortunately not even possible for really any activity, least of all dating - things will change and problems will appear and it's crazy to break up at the first sight of conflict, because conflict and bad feelings are inevitable, even if they're rare. that's how boundaries are set and that's part of the "grow into the person/grow into you" process you mentioned earlier.

>time is valuable [..] as a waste of time
i mean sure, but that's not anything to do with polyamory. that's just a case of partner selection. i don't think a core tenet of polyamory is to be particularly wild and lazy with selecting who you want to date, you can still exercise that belief in a polyamorous relationship.

>before i started dating WeebTrash [i knew that our chemistry would work together]
that'll change and you will have to be prepared for it. you're both big piles of feelings, thoughts and cells and all three of those will change over time and it's up to you two to RECOGNIZE that and deal with it when it comes up and accepting that even though you want to be it's unreasonable to believe that those feelings/thoughts/cells will grow perfectly in tandem for all eternity, because at some point they're gonna diverge before they reconverge.