Homeopathy's origin should be a clue to why there is no evidence to show it has ever worked.  In the words of Samuel Hahnemann, the German physician at a time when being an M.D. was not a mark of respect, believed

"The vital force that animates the healthy body, rules with unbounded sway, and retains all the parts of the organism in admirable, harmonious, vital operation . . . so that our indwelling, reason-gifted mind can freely employ this living, healthy instrument for the higher purpose of our existence."

...

"when a person falls ill, it is only this spiritual vital force, everywhere present in his organism, that is primarily deranged by another dynamic influence hostile to his life." 

So curing a disease requires a medicine that "occupies precisely the seat hitherto occupied by the derangement." It's Angels&Demons, except in the 18th century.   Homeopathy the angel replaces that old demon disease.  

To be fair, the climate for medicine in his day was no less wacky.   He couldn't have been impressed by hygiene, skull-drilling and leeches so his ingestion of a particular evergreen tree which gave him malaria-like symptoms and thus could be cured that way - homeopathy literally translated is "similar suffering" - could not have been regarded as less of a disaster than the allopathic medicine he saw in practice, where you produced the opposite effects of the disease you were trying to cure.

It's not bad logic and it wasn't even bad medicine.  For 1810.  But it's been 200 years, people.  There is overwhelming evidence now that it does not work, any more than skull drilling or leeches do.    Homeopathy has been killed plenty of times by modern science and yet it somehow does not die, the way those others did.

But why not?  Because it is impossible to debunk something that requires no evidence.  As Lee Silver wrote:

Since disease is spiritual, not material, a cure is best effected when the medicine contains no interference -- no material substance -- from the original curative agent. The greater the dilution, the stronger the medicinal spirit becomes. A dilution of 10100 (equal to the digit one followed by 100 zeros) is spiritually potent, but a dilution of 10400 (a number equal to all the particles in at least 10200 universes as big as our own) is even more potent. Hahnemann was adamant that material medicines couldn't cure disease, but he accepted mesmerizers as a valid homeopathic alternative. 

Magic water cannot be killed, though many have tried. 

And now there is one more stake being driven into the heart of this undead beast that, ironically, does not actually help anyone else to live longer.   Doctors attending the British Medical Association(BMA) annual conference voted that manufacturers and pharmacies should be forced to label homeopathic remedies as 'placebos'.   And the NHS should no longer pay for homoepathic remedies at all.

In a system where everything is free, people are able to try the kooky because it is free.  If they have to pay for it, people instead might go for evidence-based medicine.   Obviously the real problem is that homeopathy is a distraction for doctors - arguing with patients about it and having to clean up the problem after it does not work.  But homeopathy advocates have successfully managed to muddy their voodoo with herbalism and natural medicines to try and give it some validity.

The voodoo comparison is not fair, I know, but I am not the first.  Dr. Tom Dolphin, on the BMA's junior doctors committee, once described homeopathy as witchcraft and now has decided to apologize - to witches.  "Homeopathy is not witchcraft, it is nonsense on stilts,” he said.  

But it gets better.

"It is pernicious nonsense that feeds into a rising wave of irrationality which threatens to overwhelm the hard-won gains of the Enlightenment and the scientific method.    We risk, as a society, slipping back into a state of magical thinking when made-up science passes for rational discourse and wishing for something to be true passes for proof.”

Nicely put.   You don't screw with the Enlightenment in this community and get away with it.

Homeopathy advocates in England engage in some odd logic - they say anti-depressants don't always work either and the NHS spends 50X as much on those, so homeopathy should be allowed.  Which is not exactly a ringing endorsement for magic water.