The purpose of life cycle costing is to calculate end to end cost of the product rather than the cost of the project. The other way to elaborate this concept is the cost of the entire life cycle of the product not only project to produce the product.
The common mistakes most project managers do to reduce the cost of the project by sacrificing important factors such as risk and performance. As a result, the maintenance cost of product life cycle increased due to low quality standard product.
For example, if you have planned to complete the project at low cost say USD 10,000 by reducing the quality however, the maintenance cost is USD 50,000 rather than USD 15,000 over the product’s life. The maintenance could the same as planned or even below if the project manager’s delivers the product of high quality without reducing the cost of the project to create product.