Being someone whose agreements can be relied upon—who fulfills obligations even when difficult, who does not abandon commitments when circumstances change—is understood in Japan as fundamental moral quality, not merely practical reliability. Unreliability marks serious character flaw.
This creates strong pressure toward reliable fulfillment and high costs for agreement failure. When making agreements with Japanese partners, understand that your reliability will be assessed as indicator of your character. Fulfill what you promise.
If you cannot be certain of fulfilling, do not promise. Your trustworthiness, once established or damaged, will shape all future interactions.