It's not a guaranteed refund. It's just another dispute resolution, but done by the card issuer rather than the merchant. Often they will side with the consume

It's not a guaranteed refund. It's just another dispute resolution, but done by the card issuer rather than the merchant. Often they will side with the consumer and will refund the charges through their various policies, but they also investigate the case and will let the payment go through if there's no actual problem found. There are plenty of cases where consumers didn't even contact the merchant at all and yet still chargeback.