Winterizing your home is important to keep your pipes from freezing. Make sure to remove the hose from your spigot so water doesn't get trapped and freeze inside your pipes. You can turn off your outside water source as well to reduce the chance of water flowing through your pipes to your spigot.
Frozen pipes can cause the pipes to burst or cause problems with water pressure and water flow through your home, not only during winter but for years to come. Trapped water and ice can also cause mold in your pipes because of water vapor.
This doesn't only apply to single family homes, if you live in a condo you may also have an outside spigot that can affect you directly, weather it is freezing pipes, mold growth, or a higher water bill due to ice built up. These will cause lower water pressure and slower water flow. Make sure to check your HOA documents for you outdoor water system and stay safe this winter!