forecast cash outflows

I couldn't help noticing a wide divergence in the past quarter between the forecast operating outflows and the actual outflows.

June 17: Forecast - 1,112 (Actual - 1,948)

In particular, product and manufacturing cost forecasts have proven very wide of the mark in the last couple of quarters.

March 17: Forecast - 534 (Actual - 143)
June 17: Forecast - 434 (Actual - 1288)

Any thoughts as to why this might be so difficult for the company to forecast accurately? What do people think of the current forecast for this quarter? - 1096 outflows in total and 400 for product and manufacturing.