These are all very good reasons posted below, but I believe that the most important reason is corporate mindset . The powers that be - mostly old-hands- view software as physical "property" and unwilling to let go. Sharing it is seen as sacrilege! Also is seen as providing competitors a peek under the kimono and giving them an advantage.
It is the same reason that many pharmas don't release the data of their failed trials. How much better the world would have been had we had a commons of the failed drug trials. sigh
It is the same reason that many pharmas don't release the data of their failed trials. How much better the world would have been had we had a commons of the failed drug trials. sigh