A method begins by a processing module receiving a data retrieval request and determining a read threshold number of dispersed storage (DS). The method continues with the processing module sending read request messages to DS units and receiving encoded data slices to produce received encoded data slices. The method continues with the processing module determining an incremental number of encoded data slices based on the number of received encoded data slices, determining an incremental number of DS units, and sending a read request message to each of the incremental number of DS units when the number of received encoded data slices compares unfavorably to a decode threshold number. The method continues with the processing module dispersed storage error decoding the received encoded data slices to produce data when the number of received encoded data slices compares favorably to the decode threshold number of encoded data slices.