Do actors always have to find new assistants when filming new plays?

No, the reason for this illusion is that when filming a new play, there are often new brokerage companies involved in the preparation of the crew, and when preparing the crew, the brokerage companies have to provide artists' assistants for the big-name actors. Whether they have their own personal assistants or not, the brokerage company should provide them with new artist assistants in the crew to manage their affairs in detail. However, if some brokerage companies are short of staff, they may find new artist assistants, which will give you the impression that stars need new artist assistants to shoot new plays. The way to find these new artist assistants is not to recruit from the society, but to coordinate from the circle, borrow from other companies, arrest people from friends and so on. Because these artist assistants can't be done by outsiders.