“Putting the customer at the heart of everything we do” is the boilerplate response of choice for new chief executives. Antony Jenkins said almost precisely those words when he became the CEO of Barclays in 2012, just four years after the financial crisis blew a hole in the global economy. 

Saying something and doing something are very different. Few businesses die through the lack of good ideas. They fail through the lack of execution. And that is often down to technology. 

Jenkins had a 30-year career in what might now be described as “legacy banking.” He left Barclays in 2015. And if he had learned one thing, it is that there was a major problem lurking at the heart of nearly all large-scale, long-history businesses. It is the “spaghetti systems” issue—computer refits and technological upgrades that have been built haphazardly over time, one on top of the other.  

“Much of it had been created in the 70s and 80s,” Jenkins told me of the computer systems that underpinned much of banking then. “Some of it even went back to the 60s. 

“I was worried that as technology made lots of things possible, we as incumbents would fall further and further behind. And you could see that manifest itself as banks responded firstly to having to deliver services over the internet and then over mobile—which they did, but they did it in a very expensive, slow, and costly way. And I lived through all of those experiences in my first career in the banking industry. 

“It’s a bit like a cathedral. When you look at a cathedral, it’s all beautifully built. But actually, it’s generations of people who have added a gargoyle here or a spire there and that’s exactly how these systems started off in the banking industry.” 

“Take me back to the start,” Coldplay sang in Scientist. Many C-suite executives know they should restart whole technology systems in their business, an imperative even more important now as AI agents demand new ways of looking at technology enablement. Many C-suite executives also know the often risk-averse world they operate in. Caution is the enemy of innovation. 

“In a big bank, if you want to deliver a new product, a new variant mortgage or a credit card, it can take you nine months to a year to 18 months to build and deliver that,” Jenkins said. 

“I wanted to be able to do that in a few minutes. I wanted to be able to build beautiful user experiences without having to put a whole bunch of technology between the legacy systems and the new system. And perhaps most importantly, in this era of AI, get to data in real time.” 

Greg Jackson, the founder of Octopus Energy Group, said that true disruption is often only possible by finding a greenfield site and starting again. Jenkins launched 10x Banking a decade ago—a banking platform which provides new ways of organizing core services and customer interfaces which legacy systems find almost impossible. Clients include Chase U.K., Old Mutual and Westpac. A £50m raise in 2024 valued the company at north of £500m ($663m). 

“Technology allows you to do lots of things, but it’s only really worth doing if you are going to make things a lot better.” 

Antony Jenkins

“Today, most bank systems still run a hybrid of batch and semi-real time,” Jenkins said. “Our platform runs in real time, and our clients can look at what’s going on at any point in time. And then [see] if they want to apply AI agents to create a set of outcomes that are better for the customer. 

“When I concluded [in traditional banking], I became convinced there was an opportunity to create a set of technologies that would transform how banking gets done, and that was the genesis of 10x Banking. 

“Technology allows you to do lots of things, but it’s only really worth doing if you are going to make things a lot better. Hence the name, 10x Banking. We wanted to make things 10 times better, not just a little better.” 

Jenkins started 10x Banking with a blank piece of paper on his dining room table. Many C-suite leaders of legacy businesses would be delighted to do the same. 

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This story was originally featured on Fortune.com