Systems and methods for enhancing soft decoders and detectors on asymmetric channels are provided. The methods include acquiring log-likelihood ratios (LLRS) for error-correction code (ECC) encoded data symbols, selecting a quality measure function and a quality threshold based on the LLRs, applying the selected quality measure function to the LLRs to obtain quality measures, comparing the quality measures to the selected quality threshold, and updating the LLRs for selected ECC encoded data symbols based on the comparisons. The updating may occur by multiplying the LLRs for the selected ECC encoded data symbols by a selected scaling factor.