I tried making making this argument for many of the reasons

that were suggested in this thread and my advise was taken during a consolidation exercise.

I had one poorly designed unstable Database, etc. THis Database was a revenue generated.

The audience were Network Admin's so I tried to make and analogy.

You want to make sure that the Databases that you place a a Server Play nice in the Sandbox together.

It respectfully stated that if you put an unstable resource hog on a Server with other mission critical Databases then you put your Business at risk.