Sales and Strategy Forecast: If you have a target to achieve you can plan out your work according. It's just like keep the figures real and amenable. Unrealistic figures would not help you ever to get the target on time. Secondly with these forecast, you can compare your marketing strategies and come up with the best solutions for future activities.
Even though it is perfectly acceptable and is a common practice to use the 8_stage classic model for the e_marketing plan as well, you might want to consider the simplified version proposed by Chaffey, who identifies four major steps to build the e_marketing plan: