Younger partners may be searching for someone who is their superior, either socially or financially more secure, or to provide critical life guidance.
Some older partners may seek the connection with the culture of youth, maintaining a connection with the fashion, the music, the media which their age group has ostensibly outgrown.
They view the generation gap as an obstacle to overcome, especially if they feel they have "missed out".
They may seek the sexual vigor of the young, which partners of their own age group may no longer possess.
Younger partners, on the other hand, may be seeking a parent figure, or just somebody to provide life guidance.
of lesser status, with the stipulation that wife and children have no claims to his titles or possessions or dignity.
Still common at the beginning of the 20th C., the practice is now rare.
Women generally begin to lose fertility as they enter their late twenties, and lose it completely after menopause, while men remain almost fully fertile until much later in life.
Evolutionary psychology suggests that people are more likely to be attracted to people who look like they might be fertile.
Age disparity in extreme cases may be seen as dysfunctional (a paraphilia) if such relationships are pursued to the exclusion of all others and to the detriment of the partners.