I’m not very well-versed on all this but it seems

Edit: I don’t think this is the best, its just all I’m generally familiar with

First Past The Post

Benefits the two parties in a two-party duopoly system like that of the US. Boom or bust, black or white. When the party in power pisses you off you vote their competitor even if holding your nose.

Seems like there must be a better way, maybe just not as good for those who prefer shooting fish in a barrel