THE LOGIC OF PRODUCT-LINE EXTENSIONS

In the last ten years, products have proliferated in every category of consumer goods and services, and the deluge shows few signs of lettin g up. Most companies are pursuing product expansion categories - in pa rticular line extensions - full steam ahead. But as John Quelch and Da vid Kenny argue in ''Extend Profits, Not Product Lines'' (September-Oc tober 1994), evidence indicates that such aggressive tactics can be ha zardous. Quelch and Kenny offer several guidelines for avoiding the pi tfalls of wanton line extensions and sharpening product line strategie s: improve cost accounting, allocate resources to popular products, re search consumer behavior, coordinate marketing efforts, work with chan nel partners, and foster a climate in which product-line deletions are encouraged. In this issue's Perspectives section, nine experts offer their views on product-line management and the logic of line extension s. Some excerpts: ''In many markets, the development of product-line e xtensions is a competitive reality. As product categories evolve, a co mpany must continuously adapt its product line.'' Bruce G.S. Hardle an d Leonard M. Lodish ''Marketers would do better if they thought of the mselves as biologists studying the evolution of a species rather than as accountants studying each element of cost.'' David R. Beatty ''As t hey consider new products and services, managers must carefully evalua te not only how the brand affects the line extension but also how the line extension affects the brand.'' Laura S. Wicke