Profit - Economists versus Accountants

Normal profit to an economist represents the average reward of entrepreneurship.

To an accountant, profit is the difference between cost and selling price.

But economists include normal profit as an element of cost, this drawing attention to the entrepreneur's desire for profit. If profits in an indistry are abnormal (or supernormal), new firms will be attracted; if they are subnormal; the less efficient companies will tend to leave the industry.

Therefore how can one better understand 'normal profit' on top of the definition given above? Normal profit represents a position of equilibrium where the movement of firms into and out of the industry is negligible.