Entrepreneurs contribute greatly to society by turning demands into supplies, creating jobs, innovating new products that improve lives, providing venture capital funding, and contributing to economic development. They take on risks like decision-making and pivoting businesses, but also help mitigate uncertainty through customer empathy, preference monitoring, and timely changes. Successful companies like Uber, Starbucks, and Avon all started by identifying opportunities and pivoting their business models as customer needs evolved over time.