All of these mission and vision statements are just management makework, something for a bunch of suits to congratulate themselves on as they sit in the board room wasting oxygen.
Any business can be divided into precisely two parts, money-makers and support. In your most classic business model, money-makers are sales and production. Without the sales people, you can't sell your product. Without production, you don't have a product to sell. This is what brings home the bacon. Any other department either helps or hinders this process.
IT can provide the hardware and software to make sales and production more productive, thus increasing revenues. IT can just as easily provide non-functional pieces of crap that leave those departments worse off than if they were still using paper.
Accounting and Finance can make sure the company's resources are efficiently allocated and utillized but they can just as easily demand so much documentation and pointless paperwork that the company would actually be saving money if they junked both departments and just put a bag of cash in the lunch room with a sign saying "take what you need."
Management is the biggest sinner of all. Management should be about serving the money-makers to keep the business healthy but they are under the mistaken impression that they themselves are the money-makers and it's the rest of the company holding them back. This sort of pig-headed, egocentric thinking is endemic in American industry. These are the same jackholes who think that they can outsource all production and still have a viable company. These are the same jackholes who think their 40 hour week is worth a compensation 500x greater than the 40 hour week of the line worker.
If you want to find out what's wrong with a business, start with the smug, self-important gits in the neckties.
As for your mission statement, this one works for all circumstances: "Know who signs the check, know what they want you do to, do it well, and always look for ways to imrpove the process." Fill in the blanks for your particular business. Anything else is just wanking about.