Based upon my own life experience and from observing others who marry REGARDLESS of the amount of time spent together beforehand, I believe that no one should "tie the knot" in today's society anymore. The true meaning of marriage AND the significance of a commitment of being together with only that one beloved person for their lifetime, is no longer earnestly correlated, especially in the developed western nations.
Historically, marriage had far more signification and benefit to the married couple because it was literally entrenched as a lifelong allegiance. Couples bonded together through mutuality of character, beliefs, amenability and devotion in a way that is rarely seen today. Society has bent the rules so much, especially during the past century until now, that anyone can basically do whatever they want, whenever they want, and to the extent that it makes the statute of marriage a travesty.
Our current society is constantly changing the specifications of what "marriage" is or should be. For example, the legal system in general makes it far too copious when marriage partners mutually agree that they no longer feel the marriage is worth continuing. A "no-fault divorce" allows a couple to easily obtain a divorce - without any ramifications. Some marriages are so short, the ink on their marriage license isn't even dry before divorce proceedings begin. Since this perspective is so common today, what then, would be the purpose of marrying in the first place?
Even as recent as the early 20th century, people married and stayed married - 50 years or more was commonplace. Today, a couple celebrating their wedding anniversary beyond even 5 years is considered a 'remarkable success'. Marriage should be a foundation of sincere love, mutual respect and loyalty that shouldn't ever be taken lightly. It's such a shame that it has become a sham.