When Does It Actually Make Sense to Build a Campaign Microsite on a New Domain?

Someone in every marketing meeting suggests it: what if this campaign had its own site? Its own domain? Sometimes that's the right call — but far more often it's an expensive mistake dressed up as a creative decision. We know the cost precisely, because we launched on a brand-new domain and documented every day of it. Day one produced two impressions. Meaningful traffic took five months. Here's what that means for your campaign, and the six situations where a separate domain is genuinely worth it.