I bet that most would agree that collaboration trumps competition. Healthy competition has a place in life, but in general, if you want to do a good job or get things done, collaboration is better.
That leads me to wonder about what stands in the way of collaboration?
Lack of Experience
If you have mainly been part of competitive environments, you may not have the experience to collaborate well. Apt collaboration takes practice.
Preconceived Notions
Without an open mind to new ideas or ways of doing things, you may obstruct good collaboration. To collaborate well, you have to listen to one another with an open mind.
Divergent Goals, Vision and Mission
If you are collaborating with someone with a different goal, vision, or mission, it's likely that the collaboration won't be successful. To collaborate, you have to come to common ground with regard to the aim of your collective efforts.
Collaboration is clearly the better way to achieve a goal, but it isn't easy and doesn't always work. In the best of circumstances, it's best to work for better collaborative skills and abilities to achieve the goals you aim for.