The reasons are well known: the lingering aftershocks of the global credit crisis, tough new regulations, and persistent economic uncertainty. Indeed, by our calculations, the banking industry will not regain 2006 levels of earnings before 2015.

Yet some banks are finding a way to break out. Using focused technology and customer feedback, they are simultaneously slashing costs and doubling down on services that most matter to those customers who matter most to them.

In essence, these banks are reinventing the industry's business model to reap the economic benefits of customer loyalty. Our work with organizations in banking and dozens of other industries has found that loyal customers generate more revenue, stay longer, cost less to serve, and recommend their bank to their friends and colleagues. On average, a loyal affluent retail banking customer in the U.S. is worth nearly $10,000 more over the customer’s lifetime than one who is not loyal.

Exactly how banks can capture these loyalty effects emerged from Bain & Company's recent retail banking customer loyalty survey of more than 97,000 account holders from scores of banks across the U.S., Canada, Mexico and Brazil. The evidence from the survey – fleshed out during follow-up interviews of more than 5,100 customers to identify which types of interactions conducted through which channels earn their loyalty and why – suggests a clear agenda for banks to reignite profitable growth.

Three key priorities belong at the top of the "to-do" list of any retail bank:

First, banks need to "industrialize" the delivery of routine transactions to achieve step-function reductions in costs, while also improving convenience, speed and efficiency.

Most banks have a long way to go. Too many routine interactions, such as making deposits or withdrawals or inquiring about account balances, are still clogging up branches and call centers. These interactions have no effect on loyalty, however. Customers assume they will be handled flawlessly and see no reason to reward their bank for meeting that expectation. Such routine interactions not only drive up costs but distract employees from focusing on higher-value activities.

Yet despite years of efforts by banks to remove them from the branches, fully three quarters of branch interactions are for such routine transactions — the vast majority of which could be handled online or through ATMs. Eliminating the stubborn transactions that remain in branches may require more radical actions, such as by upgrading self-service options to reduce reliance on tellers in some branches, as is already common in Europe and Asia.

Second, banks must steadily boost their ability to deliver exceptional experiences at those critical "moments of truth" that matter most to consumers, such as replacing a lost or stolen credit card or negotiating a loan. These comprise less than 10 percent of all customer interactions, but banks win or lose customer loyalty based on their outcomes. Moments of truth are heavily concentrated in live channels, but tend to be overlooked in the sea of mundane transactions. Employees who possess the right service skills can be retrained for more-challenging, customer-facing jobs.

Banks that use frequent short surveys to capture customer feedback following transactions at these critical touchpoints — and then channel the results back to the front-line employees and their supervisors for learning and coaching — are able to steadily improve their service delivery, further boosting customer loyalty. They can also quickly resolve customer problems, as well as gather feedback to inform everything from product design, policies and processes to frontline training and procedures.

Third, banks need to step up efforts to develop innovative new ways to deliver routine services that earn customer "wows." One promising way is by harnessing digital technology. For example, some banks are winning "wows" with popular new services like apps that convert an iPad or other tablet device into a personal cashless ATM or by enabling remote deposits by capturing a digital image of a check via a smart phone's camera.

For banks than can design and deliver them, "wow" experiences yield a double benefit. One, they generate savings because they continue to drive frequent interactions through low-cost channels. Two, they are loyalty game changers when "wow" experiences lead customers to tell their friends about the neat new features.

Larger banks hold the financial edge in developing such applications, potentially enabling them to leapfrog their smaller competitors, which typically earned higher loyalty scores in our survey.

The bottom line: Using smart technology and customer feedback to transform their business models, retail banks can begin to generate significant loyalty gains — particularly among affluent customers who are both banks' most valuable but least loyal customers.

Banks can take practical actions that produce measurable gains that start to pay off right away, but sustained success will not be quick or easy. Loyalty is a way of doing business built patiently on a foundation of daily leadership, behaviors and actions, within a culture of continuous improvement that is refined over a period of years.

But it all starts by using customer feedback to create strategies that are, well, outside the box.

Gerard du Toit is a partner with Bain & Company and leads the firm's banking practice for the Americas. Beth Johnson is a partner and a leader of the firm's customer strategy and marketing practice.