The level of the ANA recrutes was very low, many illiterate. Poorly paid (when paid) and with no real structure behind them. Senior officers mostly corrupt, an unknown number of soldiers existing only on paper so that the officers can pocket their salary, etc....
Plenty info about all that. And the Allied troops in the field were sure aware of all this, but by the time the report arrives in Washington it has been "enhanced" to suit what the politicians wanted to hear.
On the other the elite troops (S.F. , commandos) seemed to be good and have fought hard, but abandoned by their hierarchies, not properly supplied, I understand that at a moment they have given up as well.
The way the US abandoned them overnight sure didn't help !