In my experience (adding to your list): 4. We are paying big bucks to license industry-specific commercial software that forces Oracle or SQL Server. 5. We al

In my experience (adding to your list): 4. We are paying big bucks to license industry-specific commercial software that forces Oracle or SQL Server. 5. We already have the licenses available via an EA, so why not keep using the same tech for other projects? 6. We can't find highly qualified offshore labor to support FOSS software/platforms (this isn't really true anymore, but it definitely was 10 years ago). 7. We have various data interchanges with our trading partners and using X makes it easier. 8. We already have all this ingrained experience with X and we're a thin margin company already. We can't afford the switching costs. Another angle for this argument is CapEx (big purchases) vs OpEx (labor), and how corps handle IT budgeting.