Great marketing strategy is hard to develop, if it was easy, everyone would be doing it.
The difficulty lies in the need to hold several often opposing ideas in the brain at the same time, very hard for most.
First, where to compete. This may be geography, channel, product category, market segment, and so on.
Second, how to compete. This may be the media used, branding strategy, articulation of the value and differentiation of the product, which of a choice of initiatives will be followed, which measures will be used, and so on.
Following one logic is easy enough, but the necessity to reconcile and make the trade-offs and choices necessary to hold two, many of which are mutually exclusive, is very hard.