As with most strongly hierarchical cultures, teams tend to be thought of as a group of individuals working to a strong leader. The leader tells individual team members what to do and the team members report back directly to the leader. Therefore teams tend to work vertically rather than horizontally.
In any case, for a team to work well together, everybody needs to have formed a strong bond. Traditionally teams would have consisted of extended family members working together – and so the bonds were already formed. It can be difficult to bring a group of locals together who do not know each other and expect them to work easily as a team from the beginning. In such a situation, people tend to display suspicion of one another and progress can be slow.
Within any gathering of Emiratis, hierarchy will always be present and even if you wish to develop a flat system within the team, it is likely that traditional class and family issues will result in an unofficial hierarchy developing very quickly indeed.