The traditional approach to profit is to begin with sales less expenses, but this makes profit something left over with no guarantee it will be generated. The Profit First Formula changes the equation to Sales minus Profit equals Expenses, putting profit first rather than last. The new approach to managing revenues focuses on setting aside profits and using the balance to fund expenses, while also consistently working to reduce expenses to the lowest amount possible. This system is designed to build a business for long-term success by helping the entrepreneur avoid making critical operational decisions based on temporary events that lead to future cash flow problems, like a sudden surge or decline in sales.

https://accessorytosuccess.com/blogs/books/profit-first-book-summary