Clearly, what we buy has to last an awfully long time. I think it's acknowledged in our procurement process that we get the most out of our equipment, and therefore, as we procure equipment, we have that in mind. That's why the requirements are very robust: it's because we don't replace equipment often. Durability and sustainability are key factors in determining what equipment we should procure.
On December 7th, 2010. See this statement in context.