It was introduced for use on small packages where an EAN-13 barcode would be too large; for example on cigarettes, pencils, and chewing gum packets.
For items like cigarettes, pencils, and chewing gum packets, which are small in size, it was designed to use a barcode format smaller than the standard EAN-13; this is because an EAN-13 barcode would be too large for such compact packaging.