Uncertainty should be considered as a phenomeneon linked with (observed) dispersion in economic (first of all) and financial growth rates. Growth rates, especially with regard to asset values, can be expressed as negative numbers. That is, why they are interesting from the financial point of view. That is, why those negative values influence balance sheets and income statements of commercial banks and other financial intermediaries.
There are, however, certain cost of financial uncertainty, i.e. for optimal firm decisions considering production and financial risks. Alexander et al. (1986) have discussed this problem in their (very illustrative) paper. For a newer analysis see the study prepared by Arellano et al. (2012).