Thank you very much for the question.
First of all, very often it's the links with the country of origin that are involved, as well as previous trips. The immigration officer's opinion is that the individual hasn't demonstrated that they will return to the country of origin at the end of the authorized period. This may be based on family ties, ties to the country of origin, employment prospects, or other socio-economic factors in the country of origin. This is essentially what immigration officers refer to when they indicate that, in their opinion, the individual isn't going to return to the country at the end of the authorized period.