Is it Ever Too Soon ?

Couples getting engaged after only 4-6-8 months of dating isn't new to many of us but some would ask "is it really wise to rush such a huge commitment after only knowing each other after such a brief time?"

When the right one enters into someone's life, many are faced with the dilemma of trying to figure out how long they should date before getting married. 
I read sometimes ago of  an American couple that met just two weeks before they decided to get married and they've been together for more than 50years now.(and i said to myself he that wears the shoes knows where it pinches.They probably just told themselves no going back and greatly supported each other because 50years ain't joke )  
I strongly believe people should get to know themselves considering their goals,vision and aspiration  (i don't think one needs donkey years to achieve this ) not forgetting that maturity and understanding is a key factor. Dating at 19 and dating at 29 are two different things. Doesn't that mean the older one gets the less time you have to fool around which also gets me wondering about those that invested about 7years plus in a relationship and the outcome was a breakup (irreconcilable differences as they always claim  ) Did it mean they needed such a long time to discover they weren't compatible ? or could it be that one persons goals and vision changed ?


What are your thoughts on this ?
Do you really need donkey years to pop the question or get engaged ? all in the name of getting to know the person more when you already know everything loool.