Final answer:
The repeated line emphasizes that people experience loss often and become accustomed to it, indicating it's a common and inevitable aspect of life.
Step-by-step explanation:
The repetition of the line "the art of losing isn’t hard to master" emphasizes that people experience loss frequently. It suggests that loss is a common occurrence in life, to the point where it can be seen as an 'art' that one can become proficient in through repeated exposure. The line implies that loss is an inevitable part of life rather than an occurrence that requires skill or creativity to come to terms with - it happens often enough that people become accustomed to it, even if it is painful.