2. Second, it appears that life comes to an end with decline, but there are examples when after decline the product may have found new popularity and rejuvenation. Yoga, nature food, and honey come into this category.
3. Third, historical data doesn’t help to identify when a product moves from one stage to another. It makes the task of forecasting difficult.
4. Fourth, the model worked well when the environment was relatively stable, not subject to uncertainty as it is today.
5. Fifth, Reality seldom conforms to theory. Marketing executives believe in the PLC concept – but streetwise marketers point out unusual circumstances might interfere with expected life cycle behaviour. It may result in different shape of PLC.
6. Sixth, the life cycle of a product is dependent on sales to consumers. All consumers do not buy in the introductory stage. Some people buy early, others buy after their friends have bought. For any product to be successful it must be bought by early adopters.
7. Seventh, PLC is a metaphor. Products are not organic, and as such don’t have to die.
8. Eighth, the length of a product-category life cycles tend to be longer than the individual brand life cycles. A movie may be not live a long life, but movie category is more than a century old.