Until science found it so. Homeopathy is on the verge of being validated by Western science. It could use it. Homeopathy uses medicines in a way totally different than conventional therapy. Western medicines increase their effect when the concentration is increased.
Conventional medicine pushes the dose to the point of weighing the side-effects to the benefits.
And there are always side-effects in Western medicine. But homeopathic medicines are effective in concentrations as dilute as a million to one. Side-effects are unheard of. Homeopathic medicines are made from substances that are often poisonous in higher doses. It doesn't matter if the substance needed is mercury or chamomile, snake venom or tobacco, it can be diluted as much as one million million times and still be effective.