Product failure is inevitable in manufacturing and can cost companies millions of dollars, experts say. When Ford and Firestone recalled more than 14 million tires in 2000 because of tread separation, the automaker revamped its testing process, but its products still fail eventually. "Companies come to me and say they want to be 100 percent failure-free after three years. But that's impossible. You can't do it," said Fred Schenkelberg of the firm FMS Reliability.