They are using the word 'destined pairs' for people who haven't met a match for years until they met their partners with a high degree of matching rate.
It was always portrayed that they would be together and love each other for life.
Well, there were some examples of those people found in history, so they can't be seen as mere hearsay.
There are records showing that some of the guides and sentinels who have a high matching rate were matched with a lot of people, but they still couldn't find their match until later on.
It was also recorded that those people ended up falling in love with each other, and they stayed happy for a lifetime.
However, those words can't also be viewed as complete truth because some records also showed that even if the guides and sentinels have a high matching rate, they won't necessarily fall in love with each other.