The minimum amount due distinguishes you as a "good" i.e. interest paying customer of the bank who is operating within the credit limit stipulated by the card issuing bank, rather than being a defaulter, who cannot pay back anything (not even the minimum amount due for that billing cycle) to the card issuer once he/she spends money credited to him/her. Of course if you don't want to pay them interest, you will have to pay the full outstanding amount every month.
