Why was Kate Middleton called 'waity Katy '?

Kate and William were together over 8 years before he proposed and broke up at least twice. Unlike most young women her age she held only one job for a very short period & for the vast majority of the time before she was engaged she was not gainfully employed. She spent most of her time on holiday, shopping, or clubbing. Some in the media felt it was because she was waiting around on William to propose. Once she did become engaged she dropped the pretense in order to plan her wedding. The British & American press seem to have had fun poking fun at her with the Waity Katy title while William of course was exempt from any such ridicule by not proposing to his long time girlfriend. It wasn't how long they were together that caused the nickname but the fact that Kate did nothing productive with her time at all. She didn't seem to have any interests outside William, which is peculiar for someone who is supposed to be a modern, educated woman.