I've seen people list this as a goal, sometimes its because they are not happy with their life as it is presently, usually its a single thing about their life that they are not happy about, ie work, relationships, emotional state, physical health or fitness, and this is seen as central or pivotal to their life and changing it will is going to change their life.
I was thinking about it in a broader sense though and would it be possible or even desirable to actually do this? Its bound to be something which would be worthy of a book if anyone did choose to do it properly, imagine what you would have to change in order to have a totally different life, just off the top of my head I can think of career, job, profession, geographic location, social network, basic habits like time you get up, time you go to sleep, how you spend time in between.
There seems to be a lot more militating against doing this successfully than there is operating in favour of it, the whole way in which the education and training system is structured for instance I think makes it more likely that people are inflexible in their choice of skilled career paths, its also something that I dont think someone with a family or dependents could do and a lot of economic factors militate against it too, rents are a rip off and its difficult to buy and sell property if you own your home, this could restrict movement.
Its got me thinking about how free people actually are.