One enters into a marriage by one's volition - i.e. it's a choice, it's voluntary.
Marriage is a contract into which two parties enter both giving something (themselves) in order to received something (some consideration, which is supposed to be an exclusive relationship in most cases (unless one party is polygamous)).
Marriage requires effort, just like any relationship, or activity. When one gardens, one cultivates the ground, plants the seeds or seedlings, waters and fertilizes regularly, weed the ground, and then harvests the produce. The ground doesn't prepare itself, and plants don't plant or harvest themselves.
Marriage is about giving and receiving tender loving care (TLC).
But as we have seen many examples, marriage may not be for everyone.