If you could decide, How and why should a couple fall in love?

I think it really depends of the situation and the people. ;)

Why a couple fall in love is c=because of the charackter of the other person. That should be more important than the body or something else. But there must be an attraction or it wouldn't work ;)
How... I think the most romantic thing is a love that grows out of a long friendship. They just know that they are the best friends and that there is more and more things they love of the other person. :)

So I think that is a kind of answer you expected or did I understand it in a wrong way?

the most meet physically or through any means of communication. they most learn to love each others character, they most learn tolorate each others faults, appreciate, resect and be attracted to each other.