Last year, Toyota Motor Corp. effectively turned a sterling reputation for producing high-quality automobiles and a loyal customer base into a brand  associated with defective cars and failure to inform owners of life-threatening flaws with accelerators and brakes.

Now Toyota has stumbled again.

This time, the Japanese automaker is running out of parts, forcing plant shutdowns around the world despite its famously reliable and efficient production processes. How is this possible?

Start with the obvious: the massive March 11 earthquake off the coast of Japan, that resulted in a huge tsunami striking the country and awful pictures filling television screens ...