Marginal gains theory is a concept that has been popularized by Sir Dave Brailsford, the former performance director of British Cycling and Team Sky. The theory suggests that small, incremental improvements in various areas of performance can lead to significant overall gains. The idea is to focus on making small, achievable changes that can add up over time to create a significant impact.

Successful people seek 1% improvement every day because they understand that small improvements can lead to big results. By focusing on making small changes, they can avoid becoming overwhelmed and can maintain a steady pace of progress. This approach also helps them to stay motivated and to continue pushing themselves to achieve their goals.

One example of the marginal gains theory in action is the success of British Cycling. When Brailsford took over as performance director in 2003, he set out to improve the team's performance by focusing on small, incremental improvements in various areas. This included everything from improving the riders' diets to optimizing their training schedules and equipment. By 2008, British Cycling had won 8 gold medals at the Beijing Olympics, and in 2012, they won 12 medals in London.

Another example is the success of the Japanese manufacturing industry. In the 1950s, Japanese manufacturers adopted a philosophy of continuous improvement, which focused on making small, incremental improvements to their production processes. This approach helped them to become more efficient and to produce higher quality products, which in turn helped them to compete more effectively in global markets.

In conclusion, the marginal gains theory is a powerful concept that can help individuals and organizations to achieve significant improvements in performance. By focusing on making small, achievable changes, successful people can maintain a steady pace of progress and avoid becoming overwhelmed. This approach has been proven to be effective in a variety of contexts, from sports to manufacturing, and can be applied to any area of life where improvement is desired.