Many banks are replacing traditional risk-based secret questions with out-of-band SMS authentication. The major driver for adoption of these technologies is regulation. With security and compliance comes a surge in calls by users who are locked out of their account. Without reducing challenge rates, a typical bank may suffer $3.6 million in operational costs for every 1 million online users. It then explains how to cut the associated operational costs and friction by a factor of 5 without compromising security, by leveraging the new approach of cognitive- behavioral authentication.”]
Source: https://www.bankinfosecurity.com/whitepapers/reducing-sms-authentication-by-factor-five-w-1089