An example is the supply arms race with research chemicals/designer drugs (RC). Every month, a new RC hits the streets with greater potency and skirting any previously-established regulations. The drug dealers will always be winning the potency race because they're on the bleeding edge, using the latest formulas and cutting it with experimental/unsafe/word-of-mouth additives.
The only way to win is making them free. And even then, the potency race continues. It's a ginormous value edge that the dealers have, and sadly, it preys on the most vulnerable sufferers.