For those of you who did know about the murdering case which involved the prime minister of Malaysia, Najib, please read it below.
Murder of Shaariibuugiin Altantuyaa
[link to en.wikipedia.org]

Last month, the two police officers who were convicted for murdering of the Mongolia woman, Altantuyaa, were sentenced to death. However, one of the policeman, Sirul Azhar Omar, somehow escaped to Australia to seek protection. This is very strange because how do a person fly to Australia when his passport was already confiscated?
[link to www.malaysia-today.net]

Many people here in Malaysia suspect that the police officer was sent away by Najib in order to cover up the truth. And another strange thing is even though this case was trial for more than 10 years, no motive was established as to why those two police officers murdered Altantuyaa.

So here is my theory, MH370 is nowhere near Australia. The only reason the Australia's government is so interested in "finding" MH370 is to help Najib. Najib asked the Australia's government to help him cover up the Altantuyaa case by protecting Sirul Azhar Omar. And in return, Najib will pay the Australia's government a huge amount of money. As an excuse to blind the public, this sum of money will be transferred to fund the search of MH370. Therefore, MH370 will never be found or this fund(payment) will stop. Of course, there may be few more reasons as to why they wanted MH370 to dissppeared, but the above reason is definitely one of them.