Why was the emphasis in the advertising message changed?

The introduction, in 2007, of the Apple iPhone was set to revolutionise the mobile phone market around the world. Apple’s marketing strategy from the start was to differentiate the iPhone from other smartphones on the market. Their principal target customers were middle–upper-income professionals that needed a PDA (personal digital assistant) device to co-ordinate their busy schedules and communicate with colleagues, friends and family. Their secondary consumer targets were high school, college and university students who also wanted a multifunction device.
With this group there was a certain amount of cannibalisation as they expected the iPhone to replace the iPod in younger people’s affections.