They don't fund everything. They don't fund anything in particular.
They provide the funding and the medical professionals decide how best to allocate that funding for the best results.
It's a bit different in Canada to my situation in Scotland since there is also the choice of private healthcare here if you want to pay more to skip queues etc.
Huh? NICE sets a cost-effectiveness threshold of about £20,000-30,000 per QALY gained from a drug[0]. There was even a controversy where a drug for pancreatic cancer was denied funding for this very reason[1].
They provide the funding and the medical professionals decide how best to allocate that funding for the best results.
It's a bit different in Canada to my situation in Scotland since there is also the choice of private healthcare here if you want to pay more to skip queues etc.