As already stated, your data needs to always be available to your users as they need it; however, it is equally important that it is ONLY available to the right people. Allowing outside parties access to your data not only can be compromising but very costly. In the wrong hands, outside parties can use company, personnel and customer data to scam your customer and employee base or ransom that very data back to you.
Availability allows your users to stay productive while confidentiality protects your company, customers and employees from allowing outside parties to use that same data against them in a way that can cost you and them dearly.