[quote=@DarkwolfX37]
<Snipped quote by Meta>

I'm literally having my ram maxed out by minecraft, and literally every modern game recommends 16gb. Just tell me what I should get to be able to be set for a year or three. I have no idea if I'm ever gonna clean my laptop so I don't know if my harddrive is still intact and I can't use it even though it's more than advanced enough.

[/quote]

Because MC is terribly programmed; that can probably be fixed by allocating more. If not, 16 gigs won't make it all that much better. 16 is recommended because it's future proof, but 8GB won't hinder your performance for at least two years, probably closer to five. If you want to spring for 16, it's good future proofing, but that's about it.
It's difficult when I'm not sure what you're doing. If you're upgrading, I have to make sure that what you're getting is compatible with your motherboard. If you're building from scratch, then you get to look for the cheapest and best parts.
I didn't understand this last sentence at all.