The biggest reason is the cost of the electronics. If you look at costs over a long period of time, you have not only the more expensive original purchase, but maintenance costs are usually based on original equipment price creating higher day two costs.
Copper provides a lower cost alternative. Doing a quick web search the 10G costs for the various components are shown below (this does not include any chassis or power supply – just the interface component):
|10GBASE-T||$ 10x performance at 3x the cost|
As you can see, there is quite a price jump in the various components. While the new copper 10GBASE-T components that were recently announced have various price points, the goal of the standard was 10x the performance at three times the cost.
As we all know the first iteration of any technology is quite high because companies are recouping R&D costs. However as competition takes over and the cost to manufacture the components decreases (it is cut in half over 18 months per Moore's law), we will see a marked decrease in these components over the next year or so.
ABOUT THE AUTHOR: As the Global Network Applications Market at The Siemon Company, Carrie Higbie supports the end-user and electronics communities. She has won the "Communication News" Editor's Choice Award for the last two years.