I have a coworker with an Audi that spent months without driving. For some reason, it has 6(!) catalytic converters and multiple failed. The car refuses to driv

I have a coworker with an Audi that spent months without driving. For some reason, it has 6(!) catalytic converters and multiple failed. The car refuses to drive if they are not working properly, so he had to save up to replace them all.