what are some limitations to using bollinger bands 
first bollinger bands are a lagging indicator which means they respond to rather than predict price changes potentially informing you of changes after they ve already happened in addition they can generate false signals during highly volatile market periods when the bands expand third the standard settings of bollinger bands 20 day simple moving average and two standard deviations might not be the best for all trading scenarios finally bollinger bands are often more effective when used with other indicators such as volume or momentum oscillators relying only on bollinger bands without further confirmation can lead to poor trading decisions 