Answer: Concept Development
Explanation:
The lifecycle stages a product undergoes include:
1. Concept Development,
2. Introduction,
3. Growth,
4. Maturity and
5. Decline.
The Product Concept Development phase acts as the initial stage in the Product Life Cycle, where the product concept is formulated, the product is constructed, and subjected to testing.
There is no guarantee that debt will consistently remain stable or decrease to zero; this uncertainty could reduce the portion of the 20% set aside for savings and investments. Additionally, depending on the country's economic conditions, the amount required for investments might unexpectedly increase.