What is a Product Life Cycle?
The product life cycle spans a product's whole existence — introduction, growth, maturity, decline, retirement — and typically contains many project life cycles: one to create the product, others to enhance, replatform, and finally decommission it. Product thinking manages that whole arc; project thinking manages one push within it.
The exam contrast: project life cycle ends at handover; product life cycle ends at retirement, possibly decades later.
Worked example
A payroll platform launches in 2015 (project #1), gains modules through 2019 (projects #2–6), runs profitably at maturity with only maintenance, then hits decline as regulations shift — triggering a final migration-and-decommission project in 2027. One product, a dozen projects, and the smartest decisions (like when to stop investing) were product-life-cycle calls no single project could see.