In 1994, Oregon's Umpqua bank was a minnow. It had five branches and just $140m in assets. Its business strategy was practically indistinguishable from its competitors. Nearly 25 years on, the once tiny community bank has become a giant: 300 branches, $25bn in assets and the subject of a string of articles in the world's leading business journals.

What is striking about Umpqua is that its success is not the result of some breakthrough innovation. The key to change was a series of small steps that combined to transform its branches into community hubs, hosting everything from Wii bowling nights to stitch and bitch sessions, all fuelled by own-branded coffee.