Differences between TCP and Go Back N

I read Computer Networking from Kurose and read in the TCP chapter about the differences between TCP and Go Back N. I found something that I did not quite understand. The book talks about some of the differences between the two protocols:

"many implementations of TCP buffers, correctly received, but not ordered segments, and not discarded.

suppose that segs 1, 2, ... N, are received correctly in order, ACK (n), n <N, is lost, and the remaining N-1s are won before the sender until their respective timeouts TCP relays most of seg, t .e. Seg n, not pkts, n, n + 1, ..., N TCP don’t even retransmit seg n if ACK (n + 1) arrived before timeout for seg n "

I understand the buffering of segments out of order, but I don’t understand the other behavior, and I think this is because I do not fully understand Go Back N. Following this example, if ACK (n + t) arrives before N timeout returns, the protocol will continue as if seg n was actually received, which is due to cumulative ACKS ... therefore, Back Back N will not retransmit this segment ... or am I missing something?