Under the broken windows theory, an unkempt house or area attracts a criminal element, which drives out those making a responsible living, which allows for more criminal element, and so on in a spiral. Restoration creates jobs, particularly in construction, and generates more sales (and sales taxes) for local vendors and suppliers. The renovated homes attract new populations and businesses to a region, encouraging more economic development; their higher assessed values brings more property tax revenue to local governments, allowing for more improvements and more policing.