“…Research has produced mixed and even contradictory results [ 59 , 60 , 61 , 62 , 63 , 64 ]. One strand of research defends repetition as an incentive to improve as a student, as it would increase self-confidence, motivation, a love of learning, perseverance, and academic resilience, improving wellbeing at school and encouraging new personal relationships [ 58 , 65 ]. More than a few studies have found repetition to positively affect motivational factors, reporting improvements in repeaters’ engagement and self-concept in the short- and medium-term periods [ 18 , 60 , 63 , 66 , 67 ].…”