Portugal visa applications can be refused for several reasons. Common grounds include incomplete or inconsistent documents, lack of sufficient funds to cover the trip, unclear travel purpose, invalid travel insurance, or doubts about whether the applicant will return to the UAE after the visit. Other factors may include providing false information or having an adverse immigration history. To reduce the risk of rejection, applicants should follow the official checklist closely, ensure all documents are genuine and consistent, demonstrate strong ties to the UAE (employment, family, residency), and apply well in advance.