It is always easy in retrospect to pick holes through a failed project in retrospect.
ADF capabilities are acquired against a set of requirements that ultimately have their roots in the Defence White Paper. And as has been hinted at in another reply to this thread, the length of time from project inception up until actually delivery is significant. Taking account of technology advances through project life so that you don't deliver something in 8 years time that is obsolete is not easy. And it is not just the ADF who have problems..... the list is endless. In fact the ADF probably has a better record than the US DOD.
Quite simply it is not an easy thing to do. And in the real world political considerations are thrown in as well...for example let's build submarines in Adelaide so that we can help the SA economy etc.
In summary, at the inception of each of these projects you will almost always find a team of reasonable people who think they are doing the right thing, making decisions that a lot of us would also have made in the same situation under the circumstances that were prevalent at the time.
But that was XX years ago and we now know different things than they did.