Rubinstein dispatched a team of executives to Taiwan and China to oversee production more closely. He made them redesign the battery panel on the back so it didn't squeak. And he asked for fixes to the software so it would lock up less frequently. One thing he wanted to fix was the fit of the phone's plastic pieces. When he went around the room and asked who was in charge of that, no one spoke up. Mr. Rubinstein did not relent. "I asked until I found out," Mr. Rubinstein recalled saying. "Then I said, ‘O.K., what do we have to do to get it done?'"