Sure some people buy Oracle for risk reduction after having done a sophisticated analysis, but plenty of people buy it because that's what the nice sales person tells them they need and the sales person obviously understand this techy stuff far more than they do.

The dev team says they can just use this "postgres" but the sales person said he'd seen this situation a lot of times before and that dev team was too inexperienced with "serious software" to know they needed to use a proper database rather than a toy one that people use when learning because it's free.

(not to pick on Oracle for any particular reason; this is common in enterprise sales at all levels)