Key factors contributing to the perception that EE investments are riskier than other investments include (i) the intangible nature of energy efficiency, as its 'output' cannot be directly measured, (ii) the added complexity that energy efficiency sometimes brings to operations in buildings or factories, and (iii) costs associated with additional details of preparation and implementation, plus the scale of EE projects relative to other investments. Contrary to other investments, energy efficiency cannot be directly measured in terms of incremental physical production. Rather, it is measured as a savings or decrement against a baseline of consumption or expense.