He finds four principal reasons:
1. They have a lot of money and don't want to stop doing things that made them money in the first place.
2. They are addicted to their own brands and don't want to blow them up.
3. They see everybody else as a competitor, not a potential collaborators.
4. They don't realize that innovation comes first from consumers, not themselves.
"To summarize, innovation is hampered by fear, brand addiction, paranoia, and insufficient focus on the business," he writes.