Profitable Growth Starts With Better Relationship Math

Banks can still grow by opening accounts, gathering deposits, and launching products. But a new account is only the starting line. The value shows up later: when the customer keeps money at the bank, moves money through the bank, adds services, and gives the institution a bigger role in their financial life. 

That calculation is getting more urgent as consumers spread their financial lives across more providers. In a ProSight Banking Trends discussion, two experts from Simon-Kucher said banks need a more selective growth playbook—one that looks beyond new accounts and balances to the quality, durability, and future value of customer relationships. 

Banks, they said, should sharpen how they evaluate customers: 

Know what the relationship is worth. Rohan Shah, a partner in Simon-Kucher’s financial services sector team, said banks need to move beyond basic measures such as account openings, funded accounts, balances, cards issued, or products per customer. Those metrics show activity at a moment in time, but they say less about durability and profit potential. Better questions include: How engaged is the customer? How price sensitive are they? How stable are the deposits? What is the likely lifetime value? 

Segment by behavior, not just demographics. Age, income, and wealth still matter, but they do not tell the whole story. Shah said banks should look at how customers want to manage their financial lives. Some want simplicity. Some actively shop for the best rate or rewards. Some want more help. The useful question is what financial need is becoming important to the customer now. 

Do not value every deposit dollar the same way. A long-tenured customer with direct deposit, regular transactions, bill pay, and multiple products is different from a customer who arrived for a slightly better promotional rate. Shah said balances show how much money is on deposit, but “behavior tells you the quality”—including stability, rate sensitivity, and whether the customer is building a broader relationship. 

Use payments as a foundation. Christoph Stegmeier, a senior partner in Simon-Kucher’s global banking practice, said customers increasingly expect to use multiple payment providers. Payments may not be a “wow product,” but they create frequent interaction. The opportunity is to build around those transactions with rewards, service, status, and a broader relationship that gives customers a reason to keep coming back. 

Think in terms of customer needs, not product lanes. A mortgage is part of buying a home. A small business operating account may connect to payments, payroll, working capital, merchant services, cash management, and the owner’s personal financial life. Shah said banks should look for the next customer need they can solve, rather than the next product they can sell. 

The takeaway: Growth quality matters as much as growth volume. Banks need metrics that separate durable relationships from temporary activity: stable deposits, deeper engagement, emerging needs, and long-term relationship value. Shah’s summary is a useful guide: shift from measuring product growth to measuring relationship value.