Condominium insurance provides coverage for your unit when your condominium association insurance stops. Your association typically insures the building and other common areas.
You are responsible for the interior of your unit. Typically, you need personal property and liability coverage in addition to coverage for your floors, walls, cabinets, and fixtures that your association's insurance probably will not cover.
Every association's insurance policy is different regarding what each unit owner is responsible for, so it is important to review your association policy and condominium by-laws carefully.