Marketing plan templates are developed by people who have achieved success online. They capture the lessons the author has learned along the way and save you the time, cost and effort required to develop your own. Once you have mastered a particular marketing plan approach, you can then expand by refining the template you have used or by adopting another template that might be more suitable for the marketing of a different product or service.
You can also do that if you are rushing to get a plan created. This will make your job a lot lighter because with a template, you would just be filling out a form. No need to think that hard and you can also make sure that its content is complete. Since the person who made the plan previously have revised it several times, it is sure to be accurate.