1. A method of operating a memory, comprising: reading a data set from the memory by performing iterations including sensing data in selected cells using a read bias, and producing an indication of errors in the sensed data, where a first iteration uses a first read bias; then if the indication in the first iteration is less than a threshold, then outputting the data from the selected cells sensed in the first iteration; if the indication in the first iteration exceeds the threshold, then moving the read bias and performing a second iteration, then if the indication in the second iteration is less than the threshold, then outputting the data from the selected cells sensed in the second iteration; if the indication in the second iteration shows an increase in errors relative to the first iteration, then outputting data from the selected cells sensed in the first iteration.