It is deemed to be so since both don't have an inkling on how to
sustain a relationship for the long haul. However some lucky ones
never faltered through the test of times because they have somehow
grown together as separate individuals which is helpful when you
nurture a relationship -- you get to be your own person still.
For those who have failed first loves, they use their first love experience
as benchmark for a lasting relationship with someone new hoping that
this time it will lasts for a lifetime.