Prediction isn't inherently dangerous. Any model is only as good as the data it's fed, and the person who developed/implemented the formula. However, the danger comes in when you put too much reliance on the predictions generated by a model--which may or may not be built on faulty assumptions. Furthermore, any model will always be based on past data, so the model may or may not be representative of future trends.
Find out more about the dangers of prediction in a good article here: http://awealthofcommonsense.com/forecasting-emotions/
The line "You can't predict. You can prepare" rings all too true!