The thing is that people insist on talking about "quality", when at the end of the day, people is people, not a thing. And what I mean is that words have effect on our subconscious. The second we start thingking about "quality", we introduce the possibility of "upgrading" since there would always be the possibility of something "better".

But if you see the other person as unique and right for you, then it makes sense to work in the relationship to make it work, regardless of the possibility of other people "available". You can substitute one person for another because each person is unique.

I don't know if I make sense.