Many shiduchim have been turned down by parents wanting things that didn’t make a difference to their children.
And many shidduchim have been turned down by boys wanting things that really don’t make a difference to a marriage. And many boys have overlooked flaws which do..
I don’t know if you meant it like that or if you merely meant that “the age at which they typically start dating.”
I meant that, and it’s not based on psychology, it’s based on someone whose opinion I highly value who dealt with too many bad marriages caused by the boy’s immaturity, and (unrelated) to the point at which one’s learning style is established enough to get married.