For a relationship to work really well, both people must hold the same deep seated beliefs; if they truly don’t, then some time, somewhere, one person will shock and horrify the other with their behavior.
Two economists might both see the world in transactional terms, where everything has a value, leisure time and work time are tradeoffs, and there is an opportunity cost to everything from love to diapers.
Two lawyers might see the world as a mottled field of morality, shaded from black to white, with the law as polygons that attempt to corral the blackness, but whose edges never match completely, leaving immoral actions untouched and ethical behavior subject to the law.
Two people might believe in the essential wickedness of man, and the only defense is to band together with a tribe of like-minded people who can see this and are dedicated to fighting temptation through the power of the will.
Two people might believe in the essential goodness of man, that trust and openness is the way to connect emotionally and that empathy and caring is what holds society together.
It may turn out that the lawyer and the economist are a fine fit, but that would be because they have a deeper shared value about, say, the autonomy of the individual. I don’t think it’s easy to recognize and articulate these deep values within ourselves. They are primarily sensed, and words follow on. We recognize core values in others by their actions, not their words, and this takes giving it some time to affirm that what is spoken is also what is practiced.