Why Are Most Of The Organizations Advertising Discriminately On The Basis of particular Nationality, Religion, Gender In Their Job Ad?

There are a few factors i feel are responsible for this phenomenon especially in the UAE.

1. The UAE Labour and Immigration laws - The way the Labour and Immigration laws work here sometimes restrict or make it difficult for companies to hire certain nationalities or genders. These restrictions could be specific to the company the industry. Some restrictions are labour specific while others are immigration laws. The way the system is set up here, a company can get discount on their labour and immigration fees or other benefits by having a diverse work force or hiring more of a certain nationality eg Emiratis. This is also a reason why certain job ads specify nationality.
2. Client requirements - When recruiting for a role that is client facing, the company must consider the clients preference while considering candidates for the role. For example, if the company finds that a majority of its clientele are Chinese then hiring a Chinese national or at least someone with an understanding of the Chinese culture and an knowledge of the language would make sense.
3. Job requirements - Certain roles require frequent travel at a moments notice, for such roles the hiring company will most likely look for candidates with passports that can gain entry visas into multiple countries without much hassle.

Religion is a discrimination; however, nationality or Gender is not a discrimination - nationality means qualifying to work in the country, Gender is specific to align with gender population of existing employees - say if the entire factory has women workers, the role may demand only a woman employee.

Philosophically, a Job description or specification by itself is a discrimination to select a specific choice of candidate :)

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