In most works, romance is imposed on the main characters, it is difficult to find a work in which the hero finds a partner according to his preferences.
In many cases, the partner is better than other opponents in everything and helps the hero in many situations.
So, in reality, the heroes do not have the right to choose, they are forced to agree to rapprochement out of a sense of guilt or out of a view of the best conditions.
Other heroes are in many emotional situations with a future partner, so that due to emotional instability when they are together they think that it is love.
There are heroes who are guided by the opinion of other people when choosing a partner, like those who recruit harems, they are simply looking for universally recognized beauties.
Is it true that even in fantasy people cannot choose someone of their own choice as a partner?
Even if the heroes are busy looking for ways to increase their powers or other problems, they can find time to eat and drink, so they can also find a partner, even if they are not specifically looking for one.
They should have at least some idea of what their future partner should be like, so they can see a possible partner for themselves in someone with similar signs.