transit – Does my visa status apply to all destinations of a flight whose connections have been checked at the beginning or before each flight?

For complicated reasons, I would like to buy a flight to Australia via New Zealand, but get off in New Zealand and do not use the ticket for Australia.

A problem with this approach is that I can not have any luggage because these would be transferred to Australia.

But assuming I fly without checked baggage, another problem is that I do not have a visa for Australia. Will they check it before the first leg of my trip and will not they allow me to catch the plane? Or can I fly to New Zealand because they will only check the status of my visa before my flight between New Zealand and Australia?

Thank you.