Marketing Research allow you to:

-Have and idea of your product or services acceptability
-Have a grasp of you target market, its profile, and preferences
-Have an estimate of how big or small your market is
-Have an idea of the needs and wants of the market that you can satisfy
-Decide on the best entry strategy for your business
-Find a means to differentiate your product or service from what is existing
-See if you have enough resources to be in the playing field
-Check if you have a fighting chance against the competition
-Find out if there would be other possible hindrances to starting your business


Source: Ultimate guide to starting your own business 2007