This document contrasts how startups and large companies operate. Startups are constantly searching for and testing business models through customer development and agile development methods. In contrast, large companies execute established business models through traditional planning, accounting, and management processes. The founder of General Motors Billy Durant took risks and had success early on but was ultimately fired twice. In contrast, Alfred P. Sloan brought stability to GM through processes like cost accounting and helped transform it into a large, profitable corporation. While startups focus on discovering problems and solutions through iterative customer feedback, large companies focus on executing known business plans and expanding existing markets.