Tracking the right numbers helps explain how a digital marketing campaign is performing. Traffic shows how many people visit a website from ads or content. Click through rate explains how many people click an ad after seeing it. Conversion rate shows how many visitors take action, like buying or signing up. Cost per click helps measure spending on ads. Bounce rate shows if visitors leave too fast. These numbers together give a clear picture of success. Watching all of them helps avoid wrong conclusions. Which metric should matter most for growing a business?