Business decisions aren't just what's initially cheaper. There are dozens of factors that need to be weighed in, such as:
- TCO (Total Cost of Ownership)
- Migration costs (If it costs $400 to upgrade a machine the MS way, but 40 hours to retrain each user to Linux . . .)
- Compatibility. (OpenOffice and StarOffice are 99.9% compat with MS Office. Some companies cannot bet on the 0.1% chance)
- Client requirements. (You might lose a contract if you're not seen as using the "right software".)
All sorts of reasons why FOSS isn't chosen in the marketplace that have nothing to do with price of acquisition or technical merits.
My criteria for good software:
- Does it work?
- Can someone else come in, make a change, and be reasonably certain no bugs were introduced?