Stem cell therapy has been taken as a highly promising area of future medicine due to its potential for providing new therapeutic modalities for debilitating, incurable diseases. In addition, stem cell therapy holds promise for its great industrial value due to the rapid growth of the market size. Recently, various types of stem cells such as induced pluripotent stem cells are being developed based on the conceptual revolution with regard to cell fate decisions. However, so far, most stem cell therapies have been performed using tissue-specific adult stem cells. Nevertheless, except for a few cases of stem cells such as hematopoietic stem cells that can regenerate hematopoietic tissue, a large proportion of stem cells, especially mesenchymal stromal cells, primarily work through paracrine functioning. The short life span of the injected stem cells and their paracrine mode of action pose a limitation to the maximum therapeutic efficacy that can be achieved from the current stem cell therapy model, warranting further research and development to enhance their efficacy. Despite the fact that stem cell therapies largely remain in the research stage, the public has expectations of rapid results and even fanaticism, leading to unauthorized stem cell practices and medical tourism. Moreover, the temptation to expedite the industrialization of stem cell therapeutics by simplifying the authorization process could increase the risk of endangering the rights of patients. Thus, stem cell therapy can become a 'hope' when society can overcome the stem cell 'hype'.