Somewhat high vacancy rates are good if they're 'organic' -- if they're simply the result of there being more supply than demand. When that's the case, tenants

Somewhat high vacancy rates are good if they're 'organic' -- if they're simply the result of there being more supply than demand. When that's the case, tenants and prospective tenants have more leverage, and landlords compete for their attention. Conversely, if supply is too low, it's tenants who compete for landlord attention.