In this paper, we consider a number of causes which can potentially explain why human capital accumulation policies might have limited effect on economic growth. Mixed empirical results can be found in the literature, both supporting and questioning the key role of human capital as an important cause of economic growth. We focus on the latter and start from pointing at inaccurate indicators of human capital accumulation, such as the average years of schooling, which might not reflect with acceptable level of accuracy the level of human capital accumulated in a particular economy. We then consider the role of other causes of economic growth, such as property rights protection or financial markets development, which might affect the demand for human capital, thus potentially limiting the effect of a policy affecting the supply of human capital. We then discuss the efficiency of human capital distribution among various activities in a particular economy and argue that the way the economy uses its human capital stock might matter for its growth rates. Finally we point at potential flaws in education policy, which might result in slow accumulation of human capital.