Payment networks, retailers and banks will continue to face significant costs to address fraud as hackers find new ways to steal data, according to Byron Pollitt, chief financial officer of Visa Inc.

“This is an investment cycle that never ends,” Pollitt said Wednesday at a technology conference in San Francisco. “The resourcefulness, the intellect, the level of innovativeness in the fraud sector is absolutely amazing.”

Lenders and merchants are under pressure to convert from magnetic strips to microchip technology that thwarts hackers after millions of consumer records were breached at retailers including Target Corp. One reason the conversion hasn’t happened yet is because it’s expensive for merchants to upgrade their systems and for lenders to issue new cards, said Pollitt, whose company is the world’s biggest bank-card network.

“It’s high investment, and in the absence of a Target catalyst I doubt that we would be on the track we are on today,” Pollitt said. The chip will address about 70 percent of fraud, he said. Including a requirement that consumers enter personal identification numbers would “dramatically” slow its implementation because about two-thirds of retailers don’t have the necessary equipment, Pollitt said.

American Express Co., Visa and MasterCard Inc. have given most U.S. merchants and issuers until October 2015 to adopt chips—named EMV for founders EuroPay International, MasterCard and Visa. Those that refuse would assume liability for counterfeit card transactions.

They are also pushing retailers to use “tokenization,” where some account information is replaced with a digital ID for online and mobile purchases.