As you well know most of the money that buys the street lights, pays the policemen and firemen, operates the school system and repairs your roads, comes from your pocket in the form of local property taxes.  Every year when your taxing bodies determine their budgets, they are deciding what services you will get and how much you will pay.  The amount you pay in taxes is determined by the amount of money required by the taxing bodies to provide the needed services as well as the assessed market value of your property.  This is to ensure that every property owner pays a fair share of the cost.  As neighborhoods improve or decline and home and business owners improve their property or let it fall into disrepair, appraised values change.  Unless those values are updated, property taxes will not reflect the worth of the property and will be unfair.  The Assessor does not create value.  The value of your property is determined by the market itself.