"It was a shambles, a shambles of command, control, co-ordination and intelligence."

That was the damning assessment of one seasoned counter-terrorism expert who'd followed the Lindt siege coronial inquest from start to finish and spoke to Fairfax Media on the basis of anonymity this week. Others have used blunter language. "Man that was a f--- up," the tactical officer known as Officer B allegedly told a paramedic, shortly after police stormed the cafe. In evidence he said he had not used those words but might have said it was a "f---ed up situation [because] no one wanted to go into that cafe".

Whatever the language, one thing is clear: on the evidence before coroner Michael Barnes, the management of the Lindt cafe siege stands exposed as well short of the finest hour for the state's police leadership.

The ramifications go well beyond an overhaul of counter-terrorism management and capability. They go to the fraught question of succession. Both Police Commissioner Andrew Scipione and the woman once deemed likely to follow him into the role, Deputy Commissioner Catherine Burn, have had the sheen taken off them in public hearings before Barnes this week.

And other law enforcement agencies at the national level and around the country have been watching closely.

"The widespread view in law enforcement ... not just in this state but nationally, is that there is a crisis of leadership in the NSW police and it hasn't just emerged because of this: it has come about because of a number of historical events," says an observer with close knowledge of the force.

Key among those "historical events" is a long-running feud that erupted between Burn and Nick Kaldas, until recently another deputy commissioner, over a police internal affairs investigation in the late 1990s. Kaldas, unjustifiably as it later emerged, became one of the unwitting targets of that investigation, named in no fewer than 80 bugging warrants sought during an operation of which Burn was team leader.

"Scipione did not put a stop to the internecine warfare that was going on between Cath Burn and Nick Kaldas," says the source. "It was incredibly destructive, and polarising for the entire NSW police leadership team, and it was allowed to go on for years."

Kaldas, an Arabic-speaker who had worked closely with Sydney's Islamic communities, departed the force only this year to pursue an international policing post , his reputation intact but reportedly worn out by the internal battle. He was off duty sick on the night of the siege. But he followed events closely, at one point ringing in to convey an offer of help from religious leader the Grand Mufti.

No one disputes the bravery of the police tactical teams who were on the frontline that night and stormed the cafe in the early hours of December 16, 2014. Having waited hours in a nearby vehicle bay for an order to go in, loaded with weaponry and on high alert, they testified that they expected to die that night, still believing gunman Man Haron Monis to be armed with a bomb.

But for those higher up the chain, the coronial inquiry - triggered by the deaths of cafe manager Tori Johnson and barrister Katrina Dawson (who perished from police bullet fragments) - has been an excruciating examination of decisions on the night.

Why did police wait for a hostage death before they stormed the cafe? Why did senior commanders decide not to approve a so-called "deliberate action" that would have given tactical police commanders the option of bringing the siege to an end at a time of their choosing? What were the barriers to a greater role for the defence force? Why were technical and equipment failures not notified on the night to senior commanders - particularly Burn, who had line responsibility for resourcing these areas? Why were the resources of agencies such as ASIO apparently not tapped at the earliest opportunity? Why were third party intermediaries, such as the Grand Mufti, not utilised? Why did senior police stick so long with a "contain and negotiate" strategy that might have worked well in the sieges that NSW police had encountered to date - mostly of the domestic violence sort - but which, as the hours dragged on, became increasingly ill-suited to what was shaping up as the most critical terrorist incident yet to occur on Australian soil?

"Counter-terrorism capability is a system of systems, with complex moving parts, and different operational and tactical units required to work together seamlessly in live time," says the expert source. "What we saw revealed at the Lindt inquest is that this did not occur. It was broken and needs to be fixed."

Scipione and Burn were the final witnesses in the long-running inquiry, which heard from 119 witnesses over a total of 109 hearing days, spread over 15 months.

Giving evidence about their role, both took a strikingly similar tack: that despite their positions at the very top of the police hierarchy, neither issued any orders that night because that was the preserve of operational commanders. Burn said she had been assigned the role that evening of liaising with the state crisis committee (which includes NSW Premier Mike Baird and other ministers) as well as federal and interstate agencies and the media.

Scipione said he did not have the requisite expertise, nor would it have been appropriate given his many other responsibilities. Yet both held reserve powers by virtue of their office to issue orders if they thought it necessary, as Burn acknowledged in evidence. And both said they were there to provide advice and support as needed.

Despite this, neither took steps to follow up on the failure of senior commanders to approve a controlled deliberate action plan (the DA) before Burn and Scipione went home to rest between 10.15pm and 11.30pm on the night of the 15th.

Even though police negotiators had failed to strike up direct contact with Monis as the siege dragged into its 13th hour, Scipione sent Burn a late text which seemed to reflect an assumption that the situation would hold till the morning. "See you bright and early in the morning" it finished.

The fact that a DA was never approved for police to have in their back pocket on the night has deeply upset the Johnson and Dawson families, if questions asked by their lawyers during the hearings are any guide. One police expert told Fairfax Media he believed it "unprecedented" for there not to have been a DA. "It should have been up there clearly on the whiteboard."

Senior police gave evidence that they persisted with their "contain and negotiate" strategy because they still felt it held out the best prospects for a peaceful resolution. But as another expert source points out: "In 14 hours, they had not got into a conversation with the perpetrator. If that was a strategy, it was not working. If not for the fact that two innocent people lost their lives, it would be risible. Where was their plan B? It was an abrogation of responsibility. Can you imagine somebody in French or British policing having the temerity to say this in a command role?"

The "see you bright and early" text was controversial for another reason. It is the only one that has survived from the phone Burn was using that night. She says she deleted the texts from that period, regarding them of no importance, having been told the morning after the siege that she would not be deemed an "involved officer" in a critical incident inquiry. So when the text turned up last Tuesday morning it landed like a bombshell.

Burn said she had forgotten about it, but that it survived because she emailed it to herself at 10.57 on the night of the siege. It is still not clear how and when police unearthed it. But Jeremy Gormly, SC, counsel assisting the inquiry, was visibly annoyed, particularly as it revealed Scipione had visited technical officers at the forward command post at the height of the standoff and discovered they had had to borrow equipment from "another agency" (which was not identified) - apparently to deal with deficits in audio and visual surveillance of the cafe. "You knew your texts might have been relevant to police reviews?" Burn was asked. "I did not assess that was the case," she responded. Yet according to several sources consulted by Fairfax Media, "policing 101" should have dictated the retention of such texts in these circumstances – even if only to prove later, as she asserted, that they had no significance.

Another area of confusion was over the triggers for an emergency action, or EA, which police finally launched after Tori Johnson had been forced to his knees and executed at the point of Monis' sawn-off shotgun.

The inquiry heard different officers had different views as to what the emergency triggers were. Some thought the firing of a shot, others the imminent threat of harm or death to a hostage. In the event, when a sniper finally saw Johnson forced onto his knees shortly after the escape of half a dozen terrified hostages at 2.03am, the message did not get through to the decision-makers in time for them to order the EA. Disturbingly, the inquest heard this was likely due to radio communication problems.

Johnson died at 2.13am. A tactical commander later gave evidence that if he had known about Johnson being on his knees, he would have recommended an immediate storming of the building.

Pressed on whether she supported the inquest process this week, Burn replied "yes". But she conceded there had been "concern" among police at the prospect of an open inquiry into the Lindt cafe deaths. And when it was put to her that many police would have preferred a "quick inquiry behind closed doors" of a kind conducted by French authorities after their terrorist crises, she didn't demur. The evidence of recent weeks is a vivid illustration of why that might have been the case.

The Lindt cafe saga has served to put Baird on notice that he needs to be thinking hard, now, about a successor for Scipione. The rift between Kaldas and Burn effectively ended their chances of taking the top job when it exploded into public view. Burn appears even less feasible as a successor after this week.

Some observers believe there is no obvious candidate now within the ranks of NSW police to take over when Scipione retires next June (he has already had a two-year extension and now been in the role for nearly a decade).

Others say Mick Fuller, the force's current spokesman for domestic violence, the southern regional commander Gary Worboys and Geoff McKechnie, one of the assistant commissioners who has rotated through the acting deputy commissioner role since Kaldas' departure, could be credible candidates to step into the nearly $600,000-a-year job should there be an internal appointment.

But it is also known that the NSW government has been sounding out figures from the federal arena. One name quietly being mentioned is that of current head of the Australian Border Force, Roman Quaedvlieg.

For now, until there is change at the top, the senior levels of the force remain frozen.

Fairfax Media has spoken to several senior officers who say the instability and infighting at the top has trickled down through the ranks. They are frustrated by the little to no change in top brass - commissioner, deputy commissioner and assistant commissioner – over the past seven to five years. This has meant holding back the current future leaders of the force at the inspector and superintendent level.

"There is a whole generation of good officers who have great potential who are starting to look elsewhere because of the lack of opportunity," says one senior officer.

Another says "it's been a failure not to have proper succession planning – it should have been part and parcel of a performance agreement".

Scipione and Burn both emphasised in the witness box this week that NSW counter-terrorism capability – once the country's finest at the time of the 2000 Olympics – had been overhauled and improved since the fateful night of the Lindt siege.

What was lacking was any statement recognising that things could have been done better on the night. It was a statement that might have given some comfort to the bereaved families of Katrina Dawson and Tori Johnson.

The coroner's report is due by the end of the year.