Most buildings and property are depreciated over 27.5 or 39 years. A cost segregation study re-categorizes a portion of the building/property into 5, 7, or 15-year class lives. When the usable lives of these items are accelerated, income is reduced, thus reducing taxes.
There is no advantage in waiting 27.5 or 39 years when you can reduce your taxes today.
The American Institute of Certified Public Accountants (AICPA) and many leading financial publications, including the Journal of Accountancy, have recommended cost segregation.