That's way things are now *shrug* If your never willing to get a job you won't be welcome at a job centre...
A decade or so back it was different, if you were unfit for work you got stuck on DLA for life, no repeat assessment, you just got sent a big cheque book every year....but then it turned around and they got pelters for basically letting people rot on the scrapheap and fall through the various cracks in the system. Spend 10-20 years off on the sick and you found it near impossible to get anyone to give you a chance if you changed yr mind.
So no, you don't get to just opt out of ever doing anything, it;s massively unhealthy. Lets face it, if we're declaring folk with terminal cancer and such fit for work, what chance do headaches have?