Why, in the case of local networks, they judged that it is not necessary to systematically have a transmission protocol in DATA link layer to repeat the transmission of lost frames? And how are errors solved in this case?
Retransmission of data is left to the upper-layer protocols or applications, and not all of them do that. That leaves it up to the application to decide if it really needs all the data. There are multiple reasons:
Errors in the Data-Link layer are considered corrupt frames and simply dropped, rather than waste processing power and bandwidth for possibly unnecessary retransmission.