On the relationship between idea-quantity and idea-quality during ideation

A great deal of research has been conducted to develop methods and techniques to improve group ideation. Most of this research focuses on techniques for increasing the quantity of ideas generated during ideation; less attention has been given to the quality of the ideas produced. This focus stems from the widely held quantity-quality conjecture, that, all else being equal, more ideas give rise to more good ideas. In this paper, we argue that cognitive inertia and scarcity of solution space may affect the relationship between idea-quantity and idea-quality as ideation proceeds, resulting in a condition of diminishing returns for additional ideas. Results of a laboratory study using fourteen groups supported the diminishing returns hypothesis. Recommendations for future ideation research are suggested.