The future of iRobot Corp. IRBT, -8.77% is likely to be rocky as it faces tougher competition in the home-robotics market on its own. The Roomba maker said it will now focus on its own restructuring and becoming profitable again, after waiting almost 16 months for regulatory approvals for a proposed merger with Amazon.com Inc. AMZN, +1.34% that ultimately did not all come. The news had been expected by some investors, especially after the European Commission in November wanted certain assurances the deal wo ...