@HinchinbrookLet me help then seeing as you fail to understand...

@Hinchinbrook

Let me help then seeing as you fail to understand and don't worry, your not the only one.

To start with it's not really a tax concession and secondly it's not just for the rich as it basically applies to any type of investment in Australia, not just property.
As with any investment it has costs, costs of any investment or business are logically subtracted from the revenue streams the investment or business produces and whats left over is either a profit if the number is positive or a loss if the number is negative and when the investment or business generates a loss one is allowed to claim that loss against any other positive income one might have.

To put it simply, you can't get a tax break on a loss producing investment because one can only pay taxes on a profit thus it's not really a Tax concession.
For a house investment example there are many costs, theres insurances, property management fees, maintenance, interest costs on any borrowings etc etc .....If the costs per year including interest which is generally the highest cost is say 60k a year and the rent revenue is 50k then that investment produces a loss of 10k per year and thus it's only fair and logical to be able to write that loss off against other income one might have.

If you form policy to stop being able to write off losses an investment property creates for the individual investor then that will increase the cost of that investment, in the example i used the increased cost would be 10k, obviously investments are based upon ROI and if all of a sudden ones return on investment shrinks by 10k then that 10k would need to be replaced through the investment income stream which with investment properties is known as rent.

Because investment properties are not principal places of residence i imagine they would attract that horrible tax (Lol) commonly known as Capital gain tax thus when the investment property is sold is when the Gov would get a massive chunk of any investors capital gains profits and in effect this system actually keeps downward pressure on rents because property investors don't make the money out of renters they make the money out of the capital gain whenever they sell it and because of this property investors don't need to make sure rents are high enough to cover the investment costs

If you get losses on your share investments you can claim that loss against other incomes you have, property investment just the same, an investment is an ionvestment, doesn't matter what it is and a loss is a loss.