Problems In Using The PLC:
(a) Time period-how long is the product life cycle? years, months or decades. There is no fixed length of each stage.
(b) Sometimes you cannot tell which stage the product is truly in. Not every decline means an absolute decline or maturity. It could be temporary due to other forces in the market place.
(c) Products could show other curves other than the S curve.
(d) Product definition-the concept of product life cycle does not clearly define what it is that is being referred to by the term 'product', yet in marketing the term product could refer to any of the following:
- Product item-e.g. Close-up tooth paste, Toyota RX, or Bic pen.
- Product-line-e.g. toothpastes, soaps, cars, etc.
- Product mix-e.g. EAI range of products, Cussons range of products or Bidco range of products.
It seems that when marketers talk about a product in the Life Cycle, they are usually referring to product items or brands. It is logical for instance to argue that individual brands of cigarettes come and go than to say that all cigarettes will one day disappear from the Kenyan market.