is attempting to differentiate itself along these dimensions favorably relative to its competition. It seeks to minimize costs in areas that do not differentiate it, to remain cost competitive; or If it is focusing on one or a few segments, it is following a focus strategy. A firm may be attempting to offer a lower cost in that scope (cost focus) or differentiate itself in that scope (differentiation focus). The concept of choice was a different perspective on strategy, as the 1970s paradigm was the pursuit of market share (size and scale) influenced by the experience curve. Companies that pursued the highest market share position to achieve cost advantages fit under Porter's cost leadership generic strategy, but the concept of choice regarding differentiation and focus represented a new perspective. Origin Empirical research on the profit impact of marketing strategy indicated that firms with a high market share were often quite profitable, but so were many firms with low market share. The least profitable firms were those with moderate market share. This was sometimes referred to as the hole in the middle problem. Porter's explanation of this is that firms with high market share were successful because they pursued a cost leadership strategy and firms with low market share were successful because they used market segmentation to focus on a small but profitable market niche. Firms in the middle were less profitable because they did not have a strategy. Porter suggested combining multiple strategies is successful in only one case. Combining a market segmentation strategy with a product differentiation strategy was seen as an effective way of matching a firm's product strategy (supply side) to the characteristics of your target market segments (demand side). But combinations like cost leadership with product differentiation were seen as hard (but not impossible) to implement due to the potential for conflict between cost minimization and the additional cost of value-added differentiation. Since that time, empirical research has indicated companies pursuing both differentiation and low-cost strategies may be more successful than companies pursuing only one strategy. Some commentators have made a distinction between cost leadership, that is, low cost strategies, and best cost strategies. They claim that a low cost strategy is rarely able to provide a sustainable competitive advantage. In most cases firms end up in price wars. Instead, they claim a best cost strategy is preferred. This involves providing the best value for a