A lot of people seem to get this consciously but have not yet internalized it completely. Many people tell themselves exactly what they want in a partner or a relationship. It should be like this, it should be like that. But they forget that in order to get this kind of quality relationship, THEY as well have to become something more.
In fact, they have to become exactly the kind of person they would love to be around. If you are a rather introverted person, you might not attract a lot of social and outgoing, fun people into your life, because they might not be able to connect with you in a deep enough level to build a relationship upon it. But if you would open up and also let your true (your best) self shine through, they have a chance to really SEE you and appreciate you.
In order to make this happen YOU have to become more outgoing, more social, more fun. You have to be the person you would like to attract in your life. A lot of parents tell their childs to “just be yourself”, but to be honest: being yourself can be far from being your BEST self. A lot of people want the best out of life, but are not willing to go for it. They want this super great relationship but do not put enough energy in the relationship and foremost in themselves to make it happen. You have to invest time into yourself and stop thinking about all the stuff you want from other people for a moment. Ask yourself what you can offer in a relationship? Are you the kind of person somebody, who you would like to attract in your life, would be happy to be around? Are you the person somebody loves to be with or is there something you could work on?