[Aperocky]

Exactly, the best software products are open source, of course many bad ones are also open sourced, but proprietary software that must be kept secret -- even within the company -- are usually not the best. Even for the hypothetical scenario where they are leaked - they would only make sense in the context of your business, as such should be mostly worthless to anyone else (but it may expose the degree of competence, and potential attempts at security via obscurity, so could still be very bad news).