They are part of your branding, and just like your website, logo, and social media presence -- they should be great. Similar to the other content on your website, your nonprofit's mission statement involves strategic planning and brainstorming to truly define your core values and purpose.
Mission statements are of vital importance to nonprofit communications because they convey, in one or two sentences, the purpose of the organization and why it exists. The casual visitor to your website or reader of your brochure needs to immediately understand why you exist and who you serve - less about what it is that you do to accomplish that mission. Think of your nonprofit mission statement as your value proposition to potential supporters and partners - what would happen if you closed your doors tomorrow?
Infographic by: blog.elevationweb.org