"Wait till your birthday to unwrap your gift"
may indeed be da "proper" way of behaving, but there are several flaws with this "old school" practice, such as:
(1) Very few
people are gonna actually care nowadoys whether you and your significant other "learned da ropes" before "tying da knot"; in fact, you run da risk of being eye-rollingly called a "
prude" if you do
indeed delay "fillin' da bucket" until da official "milking time".
(
2) Da sex dat you experience before
marriage is very often much more fun and satisfying than any intimacy you engage in after da wedding, when you'll likely have more cares and responsibilities to take up your time and wear you out.
(3) You won't be able to know whether intercourse with your partner will be comfortable or even significantly pleasurable till after you've committed, and therefore you might be stuck with miserable/infrequent "intimacy". If you'd "tried each other out" shortly after you'd originally met, however, you'd have discovered if you
two weren't "compatible" in dat way, and thus you could each have
gone to seek different partners whose personalities and/or physical attributes were more to your liking in da bedroom. It's just like buying a
car --- would you sign da purchase-agreement without even taking said vehicle for a test-drive first?!