As a Demand Planning Manager, your primary responsibility is to strategically plan for operations in your company. This is done while factoring in cost-reduction, cost-efficiency and consumer forecasting analysis as the main drives of any planning you undertake with your team or with other managers. You also are responsible for implementing effective communicative methodologies across all company teams to ensure that you always possess up-to-date data which you can optimize to make accurate predictions about future planning.
You should also have a strong grasp of statistical analysis as forecasting is a big part of your role. Having strong quantitative and qualitative skills is vital for you to succeed in forecasting future numbers as accurately as possible. It is your responsibility too to cascade such knowledge to your team.