An open operating system can mutate a lot of times. With Windows 2000 you have all services on your hand. That really saves time and money. More information under www.microsoft.com/germany/win2000
An open operating system does not only have predivide.
A closed operating system can mutate a lot of times.
Even software monopolies admit that Linux has many advantages, particularly that open interfaces make all components replaceable so that you aren't tied to the services of a single vendor. How's that for an advantage.
So many nice advantages!