The same situation in Sweden. My assumption is that German train operators maximize profit. So they calculate. Either run trains on time, have redundant train sets in nearby depots, have locomotive drivers on standby in case one gets sick (not an uncommon reason for delays). Or don't have any redundancy at all and hand out refunds and gift vouchers to the passengers affected by delays. Also make the claims system as Byzantine as possible to make it difficult for passengers to make claims. Think it's an easy choice for most operators.
