National Archives of Australia

I was referred to this place to locate old records for my mum. The staff were friendly and helpful. Thank you.

Visited the place, didn't have a memorial of me.

its nice
you're welcome

I posted the following question via messenger more than 3 weeks ago and despite the automated response with words to the effect ...we'll get back to you shortly.. i have received no intelligent response.
"Why are some digital records from 100/70 years ago either non existent or unavailable.for soldiers who served in World War I and II ?
Surely sufficient time has passed for the task to be completed."
When will I receive a response.???