At the deepest level, many organisations would do well to make an inventory of the systems software which they have on their mainframes, mid-range machines, and fleets of PCs, WP equipment, workstations and network controllers. In general, they do not have access to source code for any of it. In the present state of the marketplace, that may be 'normal', but it involves risk. While ever the right people have access to the source code, it may matter very little that the ultimate user doesn't. After all, a great many users neither know about nor care about such technical matters, and wouldn't know what to do with the source code even if they had it.
Users are happy in such circumstances - until something goes wrong.
A remarkably large number of different things can and do go wrong. The most dramatic example is that some software suppliers, including some very reputable ones, have gone into receivership in the past, and some will do so in the future. By world standards, Australia has very high quality software houses, but the industry is very competitive, technology changes very quickly, and Australian capital markets still leave a lot to be desired. When companies die, the receiver searches for and makes an inventory of whatever assets he can find. So, if the source code can be found, the receiver impounds it.