Perfect competition in the long run?

Hi, I'm in my first year studying microeconomic. According to the text, in perfect competition, economic profits are impossible in the long run, does that mean, business in real world eventually goes out of business if they are not monopolistic -like?

No, it simply means that over time other entrepreneurs enter the business which is making economic profits or profits which are in excess of normal profits. By that happening more competition starts taking place till we reach a point where there are zero economic profits to be made. The businesses still function only now they function on just the normal profits which are required to keep any business running. Over time competition comes in and therefore firms cannot make economic profits in the long run. Of course this is taking into account that there are no special barriers to people coming into the businesses.