Does the initial ritual bath (ghusl) or ablution (wudu') become invalid if their renewal is not completed due to special circumstances?

Renewing ablution (Wudu') is recommended by the majority of jurists, and ablution is not nullified except by its known nullifiers. Starting to renew ablution and then interrupting it does not nullify it. As for renewing the ritual bath (Ghusl), it is not prescribed, and the jurists of the Hanafi and Shafi'i schools have explicitly stated that it is not recommended, as the first Ghusl remains valid unless something necessitating a new one occurs.