Predictive analytics uses statistical techniques like predictive modelling, machine learning, and data mining to analyze past and present data to predict future events. The quality of predictive analytics depends on three factors: the quality of past data used, the appropriate use of statistical techniques like various types of regression analysis, and the validity of assumptions made in the analysis. Issues like poor historical data, assumptions not holding true over time, and data not being streamlined across sources can create barriers to accurate prediction.