Kurt Lewin's three-stage model of change is summarized as: 1) The "unfreezing" stage where the Indian economy in 1991 was opened up, reforms were introduced, and people experienced sudden change. 2) The "change" stage where initially businesses were bewildered but eventually started understanding and accepting reforms like encouraging private investment and disinvestment in public sectors. 3) The "refreezing" stage where supportive policies reduced recession momentum and encouraged growth through policies like Make in India, formulating laws, and less restrictions.