Because It's the best business productivity suit of applications available.
Because it's more secure than Gmail and has a lot more applications included for a similar price.
Because it's familiar to your users and easy to use.
Because it will save your staff time and open up a huge tool box you didn't know existed.
Because you owe it to your staff and yourself to have the best tools supporting your business.
Office 365 is all the Office applications you've been using, Word, Excel, PowerPoint, OneNote etc as a subscription model, pay monthly and you'll never have to buy Office again as you automatically receive updates.
Office 365 for business includes emails (Exchange Online), instant messaging (Skype for Business), company cloud Document Management System and Intranet (SharePoint) but a whole other bundle of cloud applications to make business life easier. Microsoft are constantly expanding and adapting their Office 365 for business inclusions.
Benefits of Office 365