How are the pieces of the Triforce distributed?

In Ocarina of Time, it is said that Ganondorf takes the Triforce, later it explains that the Triforce split in order to prevent him from having it, and left him with the Triforce of Power because that is what he most desires. But then, how do Link and Zelda get their pieces of the Triforce? Does Link receive the Triforce of Courage and it makes him courageous? Or does he receive it because he's courageous?

Furthermore,if we assume that the Triforce gave power to Ganondorf because that's what he wanted and then distributed the other two in such manner as was necessary to destroy him we have solved the issue in Ocarina of Time, but what about the rest of the games? In Wind Waker and Twilight Princess, it seems as if they had their pieces of the Triforce all along, almost as if it is hereditary, but this does not match with the fact that at the beginning of Wind Waker it specifically states that the world is in the condition that it's in because there was no Hero of Time, which is not possible if the Hero of Time is simply a descendant of the Hero of Time.

Also, it cannot be hereditary, because even though it has never been confirmed, one of the iterations Link and Zelda (Phantom Hourglass,Skyward Sword) probably got married and had kids, given that Link and Zelda are not related, they can't both be descended from those two.

To sum up everything I just said, if the Triforce(s?) is/are not hereditary, how do they end up in the people they do?

While "Destiny" is by far the most common answer, and is technically correct, this question is more "Is there another, more thorough explanation"

This is how I understand it:

1. Ganon gets the triforce (somehow) and wishes for power. He gets only the Triforce of Power
2. The Triforce of Wisdom and Courage are now seperated and go to a suitable canidate. Courage goes to a person capable of great courage, wisdom to the person who is the wisest
3. The Triforce yearns to be complete and have its pieces together. Ganondorf knows this and feels the need to combine the pieces. Most games revolve around this theme. I believe Wind Waker had some dialogue by Ganondorf about the triforce pieces wanting to combine together again
4. Link beats Ganondorf/Ganon and restores peace.

One of two things then happen:

1) The Triforce is then combined again, later to be split before the next game or

2) It remains broken and Ganondorf is sealed away somewhere (The twilight realm, the sacred realm). The Triforce of Wisdom and Courage lay dormant and are passed down the line either through genetics or to the next suitable candidate, it's rather unclear which.

How does the triforce pieces choose their next candidate is summed up as it goes to "those that are most courageous/wise" and may not necessarily be direct descendants to previous owners. I don't believe anywhere in the lore is it stated that Link and Zelda make babies although it is heavily suggested.