Each person has to decide what they want and need in a mate BEFORE they meet someone.
If you know what you''re looking for it's easier to spot it when you see it. Yes (it takes time) to truly get to know someone and therefore it's important not to rush things. You have to see how each person handles stress, ups, and downs. You have to find out what they want from a mate and out of life in general. Most importantly you have to determine if you agree on the "major things in life".
Ultimately we are looking for someone who "naturally agrees" with us on the major things in life.