"It is personally gratifying to see that the company still has substantial value," said Paul Fiore, a founder of Digital Insight and now backer of CU Wallet, a digital wallet startup. Fiore also expressed surprise that the company sold again so quickly after Thoma Bravo purchased it, but said the price was likely fair.

"Probably Intuit left some money on the table and perhaps NCR also paid a premium, a little of both," he said, adding that he was not terribly surprised that the company had not proved a good fit at Intuit.

No one from NCR was available to speak directly about the purchase, but company executives commented on the price during a Dec. 3 conference call with stock analysts in the wake of announcing the deal.

"Frankly, Digital Insight was simply more valuable as a part of NCR than it would have been on its own as standalone company," said NCR CEO Bill Nuti when asked about the price.

Nuti and other executives pointed to industry wide data which, they said, showed that the overall payments industry was moving rapidly toward becoming more digital, integrated and online. For example, the United Nations reported global mobile penetration rates will outnumber the world's population by 2017 and mobile payments transactions are forecasted to reach $1.3 trillion by 2017.

Further, surveys have found more U.S. consumers are comfortable with mobile banking and retail, with 34% of respondents with internet enabled phones reporting they have purchased a product using their device; 58% say that they will spend as much as they have already, if not more, using their mobile phones; and, 45% say they want to be able to use their mobile phones to make transactions offline.

"The combination will help retail banks and other financial institutions reduce legacy costs and enable solutions for new, more nimble branches, by providing one platform for omni-channel services and all payment and transaction types," the executives reiterated a statement that was included in the company's announcement of the purchase.

They also made the point that NCR had purchased Digital Insight for the long term, and that the company was not looking for immediate returns on its investment and had not even forecast much revenue from the purchase in 2014.

"They have taken a very conservative position on income from the deal and that's good, because it shows they understand integration takes some time," said David Albertazzi, senior analyst for the Aite Group.

Albertazzi stressed the purchase only provided NCR with an opportunity for integration and no guarantee of success, but he added the arrangement could allow credit unions partnered with NCR to take on some abiding problems facing U.S. financial institutions.

For example, a credit union using NCR software to run its mobile banking, online banking and ATMs could potentially enable members to use the ATM to send funds to non-members.

"A member might be able to go onto their online banking site or use a mobile application on their phone to prearrange for money to be disbursed from an ATM to a person who has a given token or code," Albertazzi said. "They might even be able to prearrange for the denominations to be disbursed, depending on the limits of the ATM."

Such an arrangement could allow credit unions to offer an effective solution to the issue of real-time person-to-person fund transfers across different financial institutions, Albertazzi said.

NCR's purchase of DI could also allow credit unions, if they so choose, to move to one provider for a number of different transaction platforms instead of using multiple providers, which carry a heavier regulatory burden, Albertazzi pointed out.

But he added the deal might be a two-edged sword for NCR. Large credit unions or banks might want to have online banking or mobile banking solutions that are more customized; such customization has not been seen as DI strength. This could discourage them from having a one-firm solution, while smaller financial institutions might opt for having NCR provide multiple solutions. And, Albertazzi said, NCR could find it challenging to serve such a diverse customer base.