Some organisations such as the AAUS have recommended that a dive plan should be established before the dive and then followed throughout the dive unless the dive is aborted. This dive plan should be within the limits of the "decompression tables" to increase the margin of safety, and to provide a backup decompression schedule based on the dive tables in case the computer fails underwater. The disadvantage of this extremely conservative use of dive computers is that when used this way, the dive computer is merely used as a bottom timer, and the advantages of real time computation of decompression status are sacrificed.