I've heard the weak force described as essentially "a force between particles with flavor" just as the EM is "a force between particles with charge". Mathematically, I understand the concept of the CKM matrix being used to evaluate the weak force eigenstates of quarks, but I'm confused as to how the flavor of one of these quarks can be changed simply through an interaction with other quarks. I feel like this would be analogous to two electrons interacting through the EM force and then one of them just losing its electric charge. The best explanation I've been able to come up for myself is that one quark is eliciting the release of a W or Z boson from another quark. I'm sure this is incorrect. This is probably an utterly stupid question, but can anyone explain this to me?