Perhaps I'm not expressing myself in ways that is understood by most people. We've become too programmed by rom-coms, Disney, books, etc.
What I'm saying is that in order to have the most satisfying type of love is a marriage rooted in deep affection, admiration, and appreciation for each other. However, two people should not have to take years that include sex, spending a lot of time together, and playing house to know if they want marriage with each other. After enjoying each other's presence through conversations (and this can include being physically present), you should know that you want to do all the aforementioned with them. If you do, then you should start considering marriage because you really should only be doing those things within the context of a marriage.
The majority of people who play house before marriage end up very broken, and they carry that into all subsequent relationships, including marriage. This has already been proven true by marriage counselors, experts, coaches, etc.
When you sleep and spend time with someone, your body and your actions are making a non-verbal promise. This is where misunderstandi ngs happen and then people become broken. Even if they eventually move on to find someone else, the scar is always there. Very few people can move on from their ex(es) and it seems that the more toxic past relationships they've had, the more broken they are.
These are people who get into relationships (or rather "situationships") for the sake of breaking up.