The massive divisions between the factions within the Liberal party are part of the reason behind this mess. The ultra conservatives are no different to the Tea Partyists in the States and are driven by blind 1950s and fanatical religious ideology. They are also still bitter about their man Abbott being overthrown by Turnbull and the liberal moderates. They will oppose any move towards the political centre by Turnbull, so Turnbull has become forced by his own party to play Abbott-lite to stay PM. meaning nothing has changed.
The other reason is the LNP's own cheap political rhetoric from the last election has come back to bite them. It's hard to argue for tax reform such as increasing the GST when you've been running around for the past 7 years squealing about opposing any "big tax on everything". It's hard to argue for mature, apolitical, rational and in depth debates on important issues when you've happily parroted simpleton 3 word slogans ad nauseum since 2009 under Abbott. It's hard to argue "adults are in charge now" when you've become a government of musical chairs and indecisiveness, copying the worse aspects of the previous Labor government under Rudd-Gillard.
It's not surprising there's talk Turnbull wants these Senate voting "reforms", that heavily favour the LNP, to pass quickly and then call an early election. Getting in early while the polls are still okay and pinching even a narrow win, would give him 3 more years and most likely see the LNP control both houses. If he decides to wait the full term, and especially if the budget is another unpopular ideological-based flop, then his own personal ratings may head south along with the LNP's.