Because Open Source offers some unique advantages to the typical small & medium enterprises.

• Reduce overall cost of ownership: you only pay for the services you require!  No more license fees before you it delivers a single benefit.  No mandatory support fees.  No mandatory upgrading.
• No Vendor Lock-in: the traditional software companies can and are frequently bought and sold! And, when they are that usually means the product you and your staff have invested time & money in disappears as the new owners "encourage" you to migrate to their software - all at your expense of course.  With Open Source solutions this is not possible as the software code must be made freely available.  The providers such as OpenBiz are Service provides.  If the service provider disappears or you simply decide you wish to use another you can easily move secure in the knowledge that all the information and any new provide you choose is freely available for them.
• Flexibility: because you and your service provider have access to the source code you can create a custom fit solution that provides best support to your business.