Profit or Loss (value positive or negative respectively) is defined in accounting as the difference between revenues and expenses for the reporting period:
$$\text{Profit or Loss} = \text{Revenue} - \text{Expense}$$
Revenues are the income of the reporting period that results in an increase in assets or a decrease in liabilities and increases the equity of the entity. Contributions by owners to equity are not considered revenues.
Expenses are the outflows during the reporting period that result in a decrease in assets or an increase in liabilities and decrease the equity of the entity. Distributions to owners from equity are not considered expenses.