Under normal circumstances, guests do not need to wash the dishes when eating, because this is something prepared by the host.
In table manners, guests are usually only responsible for enjoying the food, while cleaning work such as washing dishes is completed by the host or service staff.
If the host does not arrange for someone to wash the dishes, it is best for the guests not to take the initiative to wash the dishes.
This is mainly because there is a social relationship between the guest and the host, and the guest should respect the host's arrangements and wishes.
If a guest takes the initiative to wash the dishes, it may make the host feel uncomfortable or embarrassed, and the guest may think that the host has not done a good job in preparation.
Of course, if there are special circumstances, such as a family gathering or a dinner with friends, the host and the guests can share some housework together, but it is still not recommended that the guests take the initiative to wash the dishes.
In this case, the host may take the initiative to ask the guest to help wash the dishes, or agree to it only after the guest takes the initiative.
In short, in social situations, guests should respect the host's arrangements and wishes, and should not take the initiative to do household chores such as washing dishes, unless the host explicitly requests or invites guests to help.