When you travel to UAE from Bangalore for job or business or any purposes, you need to submit various documents to UAE authorities. For example, if you are going for a job, your employer will ask for your degree certificate. If you are extending your business to UAE, the UAE authorities will ask for various commercial documents. However, these documents by itself is not legally accepted in UAE. As Indian issued documents, they do not know whether it is genuine or not. Thus embassy attestation is a method used for authenticating your documents in UAE. 

Although, there is a simple method known as apostille for authenticating documents, UAE does not accept an apostille. As of now UAE has not joined the apostille convention. Thus, an attestation from UAE embassy is the only way to legalize Indian documents in UAE.