I used to think that "culture change" was some bull**** cliche or coach speak that staff throughout the program would employ, but I believe that less and less. It's why Saban attributes his 6-6 record in his first year as Alabama's HC to players not "buying in," or more specifically why he claims that the loss to Louisiana Monroe in 2007 actually sparked a change amongst his players in which they finally realized that they needed to trust him and his staff and buy in to his/their 'process.' It's why Saban calls a sports psychologist every morning before practice or why Urban claims that his psychology degree is invaluable in this industry.
Culture is hard for people to understand and thus appreciate (like me) because it's so arbitrary and hard to define. But ultimately, and most importantly, culture sets a standard and consistent expectations. For Saban, his culture is built on meticulous and painstaking detail (down to how one dresses and eats) as well as an atmosphere of professionalism at the expense of 'fun.' His players aren't playing dodgeball and eating ice cream. For Butch, he sought to constantly reinforce that you aren't entitled to ****, but need to compete your *** of to earn your spot. Nonetheless, imo, this culture transformation shouldn't take more than 1 year.