Five years after the financial crisis, people keep asking: Has anything changed at the big banks?

Of course it has. We’ve got bigger capital buffers, revamped consumer protection, record fines, improved risk management, more transparent trading and a new tool to unwind hobbled banks. Plus we got all the bailout money back, and then some.

Isn’t that enough? 

Alas, no. Any savvy policymaker will concede regulation can only take you so far on the path to lasting change. Mind-set is the critical last mile.

And on Wall Street, mind-sets have not changed much – really, since the 1980s.

Although the fictional poster boy of that era, Gordon Gekko, makes a delicious villain, his iconic speech extolling greed is an oversimplification of what’s really driving the brain of a banker. The problems are more nuanced and harder to root out.

Perhaps the most insidious mind-set is the cult of complexity. Since computer spreadsheets took over finance in the 1980s, big banks have been competing to create ever-more-exotic new products that make big promises and earn bigger fees.

But soon it was not just about the fees – at some point, more intricate was deemed inherently better, and complexity became a proxy for intelligence. Everyone wanted to have the most elaborate structures in town. Why take direct exposure to a stock when you could create it synthetically using four different instruments? The big banks started hiring rocket scientists – literally – to keep up with the complexity arms race.

There was little consideration whether a new product was adding any appreciable value for clients or creating unintended risks in the market. In this kind of workplace, if you didn’t understand, the last thing you wanted to do was ask questions and prove yourself a fool. Besides, you’d been taught that the quant wizards – the high priests of complexity – always knew best.

Risk management has improved at most large banks, but they still have a strong bias toward complexity for its own sake. There may be rays of hope as these banks adopt mobile platforms and rely further on technology, an industry that, conversely, reveres simplicity. But until complexity is dethroned – whether driven by customers, regulators or bankers themselves – the next synthetic disaster still looms on the horizon.

Running a close second is the ethos of extreme self-reliance. You hear a common directive from Wall Street managers: "Don’t bring me problems, bring me solutions!" In the best case, this can help your employees think more broadly and proactively about solving issues. But taken to an extreme, people start concealing major problems, struggling to fix them alone, often unsuccessfully.

In transcripts from JPMorgan Chase’s (JPM) $6 billion London Whale fiasco, this dynamic is clearly on display. Already months into the bad trade, an anxious supervisor admonishes his employee for mentioning the (mounting) losses to their boss. "I don’t know why you’ve done it . . . [A colleague] told me that he didn’t want to show the loss until we know what we are going to do ... ." With a different ethos around problem-solving, this loss might really have been just a tempest in a teapot.

This ethos is not unique to JPMorgan. Financial firms need to encourage employees to raise issues sooner, and publicly praise the ones who do. Senior executives can also set a powerful example with more collaborative problem-solving in the c-suite. Sure, the cultural shift would be big, but so is $6 billion.

Equally troubling is the mind-set of universal competition. No doubt, some healthy rivalry can be good motivation and improve performance. But many bankers at the large institutions believe they are not just in competition with other colleagues or other banks, but with their own clients as well.

Bankers often look perplexed when I talk about better aligning their interests with customers. "No, no, you don’t get it. We’re on opposite sides of the trade/deal/sale, it’s us versus them." With that zero-sum attitude, no wonder they can sell toxic products without remorse – they’re just doing their job, which is to "win" the round. Industry leaders need to reinstate the notion of service and prioritize long-term relationships, especially at bonus time. 

We can – and should – continue to debate capital levels, appropriate risks and adequate protections for consumers. But policy reform efforts will always fall short until we acknowledge the power of banker mental models, and engage the industry in constructive solutions to start changing minds.

Susan M. Ochs is a senior fellow at the Aspen Institute and a former senior advisor at the Department of the Treasury in the Obama administration.