A lack of technological competition has been a strength. But as possibilities change, it's now become a weakness. As the recent debacle over CBA ATMs shows, big Australian banks struggle with innovation.This is not something you can fix overnight.This was how Ryan Dinse, the editor of the online personal finance newsletter, Money Morning, summarised his opinion piece to subscribers in a story caning the Commonwealth Bank's fee-free ATM campaign.One accusation raised concerned the apparently very "unprofessional person" who was overseeing the move to convert CBA's push-button ATMs to touch screens, as evidenced by the black background: "it's very hard to see what you are doing if the sun is shining on them," was the verdict.Other complaints have also been critical of the design attributes of the new CBA ATM's: "It looks like they got the work experience guy to design the icons" was another reported comment.All this adds up to a risk that the big push by CBA to get its customers, and those from other banks, to use a local CBA ATM could backfire. The line of reasoning being run was that the ATMs were a fail, especially for the rising tide of millennials, "used to attractive, easy-to-use designs as part of the product." (CBA was not approached for a comment on this story)