A quick look at the meanings of "ausfallen" and what cancelled meetings have to do with extraordinary dresses and electricity blackouts.
ausfallen, ausgefallen, der Ausfall, der Stromausfall, rausfallen
The core idea of this root was:
It doesn’t have any other relatives besides to fall and fallen (and “to fell” and “fällen”) in German and English and it is notably absent from the Latin branch of the Indo-European family. There, the word for falling was *kadere, which is the origin of words like cadence, incident or case.