You can learn a lot about people from what they lack. If they lack accountability, they'll shift the blame. If they lack communication skills, they'll say you're arguing. If they lack emotional intelligence, they'll call you sensitive. If they lack effort, they're not interested.
The older I grow up that more I realise a life partner is a gift from God and guides. What we think we want and need is not always the best in the long run, our guides have a sharper eye.