Have these been software companies? In software companies, software is the product. In other companies software is an expense. It makes a difference in how it is managed.

Some companies certainly are behaving better software wise. I recommend his book, he goes into a longer discussion of the details, has citations, and includes counter points. It's also possible that this has shifted since the book was written (2002 I believe), but I suspect it's more that you've been at companies who managed to get this part right.