When it comes to database servers, the well-known products have names like MySQL, Oracle, Microsoft SQL Server, Sybase, DB2, etc. If you are building a commercial product that uses a back-end database server, there is a good chance that it uses one of these. If your customer is big enough to have a dedicated IT department, it might make sense to support the database server the company is already using. If the product is going to be used across the company, this is a good thing as it makes it easier for the prospect to purchase your product since they won't get any grief from IT about it. Could using the corporate database server or some other well-known database server ever be a bad thing?
Yes, it can. In many companies, if the IT department even recognizes the name of the database server you are using, they will feel it should be their responsibility to support it. That may bring IT into the decision making process. If your product is sold at a departmental level, they may want to purchase it but have to fight the IT department because IT doesn't want to have yet another database to support. So what's the solution?
There are many IT departments that don't get involved if the product is departmental and they think the database server is proprietary. Our own REAL Server for example, comes across that way. Even though it's based on SQLite, arguably the most installed database engine in the world, REAL Server is not nearly as well-known and, as a result, comes across as a proprietary database server. This can make it easier to sell departmental products because you can keep the IT department out of the sales cycle.
We have a customer right now that is switching from MySQL to REAL Server for this very reason. That's turning a weakness into a strength!