Background: The relationship of weight loss motives with long-term outcomes is equivocal. We aimed to examine differences in weight loss motives of maintainers and regainers, as well as explore associations between motives and successful maintenance. Methods: The study sample includes 607 adults, with a history of overweight/obesity and self-reported ≥10% voluntary weight loss, 12 months before study entry. Participants were classified as maintainers (weighing ≤90% maximum weight) or regainers. Volunteers identified possible motives for weight loss and maintenance (maintainers only), from a specific list. Results: Both maintainers and regainers were predominantly motivated by physical appearance (38.6% versus 39.9%, P > 0.05) and self-esteem (26.8% versus 32.0%, P > 0.05) for weight loss. Compared to regainers, more maintainers reported weight reduction driven by social purposes (16.6% versus 9.4%, P = 0.022) and less were prompted by friends/family to lose weight (21.1% versus 31.7%, P = 0.005). In maintainers, shifts in motives from weight loss to maintenance phase were found, including an increased prevalence of health motives (6.4% versus 9.6%, P < 0.001) and decreased physical appearance motives (38.6% versus 30.3%, P < 0.001). Reporting physical appearance as main maintenance motive was inversely associated with maintained weight loss, after adjusting for age, sex and years of education (B = −3.49 [1.07], P = 0.001); maintainers reporting physical appearance as the main motive maintained 3.5% less weight loss compared to those who did not (P = 0.001). Conclusions: The present study has highlighted motivational influences associated with weight loss outcomes. Future studies should explore the ability of people with overweight/obesity to act upon motives for long-term weight management, as well as the impact of shifting through motives on the magnitude of maintenance.