When the world’s biggest carmaker shut operations affecting almost half its global production on Tuesday, investors shrugged.

This kind of nonchalance highlights the extent to which Toyota Motor has built a level of supply-chain resilience that instills confidence in the toughest of times.

A systems glitch forced the company to halt production on 25 lines at 12 of 14 Japanese plants during the day, and take all 14 facilities offline during the evening, it said. The cause of the problem wasn’t immediately known, though a cyberattack was quickly ruled out, and orders for parts had to be suspended.