Great discussion on the benefits of top down vs. bottoms up forecasting/planning. Given the highly iterative nature of the bottoms up process and usually not meeting top level management's expectations, I might offer a third approach which is top-down target setting. This would be where senior leadership provides the targets in terms of sales growth / EBITDA growth / SG&A flex as a % to sales, etc.... but then cascade these targets down to a divisional or operating unit or department level and ask for the bottoms up buildup of the forecast/plan. This might help maintain the connection and limit the iterations that senior management often drives.
