Budget fashion retailer Hennes & Mauritz was upbeat about prospects for profitability next year but a fall in third-quarter earnings and weak September sales sent the retailer's shares to a three-month low on Friday. 

H&M's results contrast with Zara owner Inditex which has consistently performed more strongly than its Swedish rival. Inditex has been able to outperform H&M in part because it can react more quickly to shifts in customer demand, making it less exposed to unexpected…