Code is not an asset
Alan Cooper has a great piece of advice for software companies: "Code is not an asset... it's your relationships with your customers and vendors and the knowledge of your people that are valuable".
The last company I worked with clearly had not grasped this concept. They let one veteran programmer after another leave without any knowledge trail for the rest to pick up. Human resource investments lost en masse.
And apparently, it was of little concern. It was always about the code. About getting it ready for another imaginary release date -- everything else expendable (people, quality, documentation).