The asymptomatic cases can also spread the disease, and a single individual is enough to trigger another outbreak if they slip through the cracks, so for contac

The asymptomatic cases can also spread the disease, and a single individual is enough to trigger another outbreak if they slip through the cracks, so for contact tracing and everything you need to know how many asymptomatic cases there might be and where they might be. And the wake might not be spread evenly throughout the population, you could end up with younger individuals being asymptomatic and creating a breeding ground for the virus to spread and mutate in a college town before, even though it seems to be under control, it spreads back to vulnerable populations where everyone is symptomatic. That's one extreme of this but we don't know without random testing how bad it is towards that end