It was 15 minutes into the phone call when Theresa May was forced to ask Boris Johnson: “Are you resigning?”

“I suppose I am, prime minister,” came the reply from Johnson, who after a weekend of pondering decided to pull the plug on his foreign secretary job over May’s Chequers Brexit plan.

The 2018 story was raised with HuffPost UK by a well-placed source in response to the question of why the prime minister is happy to U-turn on policy – 12 and counting since the start of the coronavirus pandemic – but not on his personnel.

Three sources who have worked with the PM independently note: “He hates confrontation.”

One goes on: “He absolutely hates difficult conversations, he’s not ruthless in that regard, he’s a really kind person and he only wishes, most of the time, goodwill to other people in that constantly optimistic friendly manner.

“He cannot bear to call them in and say they’ve not done the job he asked.”

It does not tell the full story of a leadership style which has left many wondering whether ministers and aides are still held accountable for their mistakes, and why the PM is so willing to spend political capital hanging on to underperformers.

The questions started with top aide Dominic Cummings’ infamous lockdown trip to Barnard Castle, and spanned a summer in which housing secretary Robert Jenrick faced calls to go for backing a controversial housing scheme linked to Tory donor Richard Desmond, and education secretary Gavin Williamson provoked a huge backlash with the exam results fiasco.

Others suggest Johnson is happy to let underperforming ministers take the flak rather than him, some see it as simply a question of loyalty and a tight “paranoid” inner circle, while a botched February reshuffle may have tied the PM’s hands until he can get through Brexit and the worst of coronavirus.

But there are plenty of examples of Johnson failing to tackle failing individuals head on.

Two sources recall an episode from Johnson’s London mayoralty, when he had agreed with a senior City Hall figure to sack an underperforming member of staff.

By the time the meeting was over, the staff member had come out of Johnson’s office with a new title and a pay rise.

Then there was February’s reshuffle, botched after chancellor Sajid Javid sensationally walked out just three short months after the Tories’ thumping general election win.

Gathering in the PM’s study, Johnson heaped praise on Javid’s role in that victory and suggested a closer involvement inside No.10 for the chancellor.

But in an almost throwaway remark at the end of their chat, the PM told Javid he would have to sack all five of his special advisers and submit to a joint No.10-Treasury team, which the chancellor refused.

The PM pleaded with Javid not to quit, even at one stage offering a compromise on the plan, but it was not enough and the chancellor walked out.

It was seen as a plan hatched by Cummings to get rid of Javid, and which could be delivered by a PM who really didn’t want to wield the knife. 

As one insider recalls: “Boris thought he was asking a relatively minor thing and he was taken aback.”

It appears to be a trait born out of Johnson’s insecurity and need to be liked, and some worry it could cost him.

“Over time, people lose respect because you have got to have a bit of a ruthless streak in order for people to understand where the power lies,” a source says.

“And my fear is that in the long term people will take advantage of him and that good nature and people think they can run rings around him, which possibly they can.”

But while some have spotted a potential weakness in the prime minister, others see his approach as a sign of strength. 

Salma Shah, former special adviser to Javid, sees Johnson as a more ruthless operator who does “what serves him best”, including getting rid of a whole tranche of City Hall staff after winning the mayoralty in 2008 with “no issue”.

“He’s not as foolish or soft as people suggest, he won’t fire people because he’s told to,” she says. 

“I suspect he will decide when people have served their usefulness and then he will act.”

Johnson may in fact be happy for underperforming ministers like Williamson or Jenrick to take the flak for the government’s mistakes.

Labour former adviser Matthew McGregor, who fought against Johnson in the 2008 mayoral election, suggests Johnson likes to disappear from view when trouble strikes.

Discussing Johnson’s election strategy, which may well apply to this campaigning Vote Leave government, McGregor once noted on HuffPost UK’s Commons People podcast that the PM “makes himself as small a target as he possibly can and just tries to dance his way through without taking too many hits”.

Johnson may be using this approach to let Williamson take the hit for the exam chaos.

“I don’t think he is oblivious to all the critics, it might feel that way, but it’s a tried and tested strategy,” Shah says.

It would certainly explain why Johnson is hanging on to Williamson despite many Tory MPs calling for his sacking in private.

One Brexiteer MP directly draws the comparison between the U-turn on A-Level and GCSE grades and Williamson holding on amid mass student protests.

They suggested the government could have held firm on using a controversial algorithm to hand out grades instead of relenting to pressure to allow teacher-assessed grades to be used – if Williamson had done his job.

“If you believe in it and you’ve thought it through properly you follow it through,” they say. 

“It was clear Gavin hadn’t thought it through at all.

“I don’t know if he’s just not intellectually curious.

“He massively fucked up and there have to be consequences for that.”

The MP notes that Williamson is seen as dangerous due to his former role as chief whip, that he knows where the bodies are buried.

“So shove him in a minister for paperclips role,” they say.

Williamson also played a key role in Johnson’s leadership campaign and the PM is keen to reward him for his loyalty.

But there may also be an element of paranoia about the Vote Leave-focused team of outsiders that run the show in Downing Street.

“They are paranoid because they can’t naturally let new people into that circle and therefore they can’t easily push people out because it will get increasingly small,” a source says.

“They think they are not perfect but it’s better the devil you know, and we couldn’t possibly let new people into that circle.”

They went on: “The loyalty is nice but it doesn’t extend itself very far.

“And it’s based on paranoia about what Gavin Williamson for example might do if he is fired.”

But a colleague does not buy it.

“The myth that Gavin is really powerful, it’s hilarious,” they say.

“Don’t take my word for it, ask 10 MPs.”

The second MP goes on: “Yes, the chief whip will know somebody had an affair and they had to pay a newspaper to hush it up, those sorts of things.

“But the prime minister really only cares about the prime minister.

“And a lot of those things got flushed out in the leadership contest.

“If there was anything about anyone that really mattered, we’d know about it.

“There will be stuff about random backbenchers, but why would the prime minister give a shit?”

They feel the PM does not want to respond to media “witch hunts” for sackings, because they simply promote more.

“You saw that with the Blair government, they never got over it because Blair got rid of people after witch hunts,” the MP says.

It is an approach towards the media certainly followed by Cummings, who is unlikely to ever get sacked, according to one source who knows the team inside No.10 well.

Again, Johnson’s aversion to confrontation is at play.

“He will never sack Cummings, ever.

“Someone else will come along and they will start to be in more of the meetings and Cummings will grow bored, tired, frustrated.

“The PM will say ‘sort it out between yourselves’ and Cummings will walk off in a huff – that’s the most likely scenario.”

In any case, most believe Johnson is likely to wield the knife in a potentially big reshuffle once Brexit is done.

At the moment, there is a feeling of “why cause trouble” with a mini-reshuffle when they have “squared off” the likes of Anne-Marie Trevelyan, who lost her international development secretary role when the department was subsumed into the Foreign Office.

There is also no need to rock the boat with the battle for Brexit entering its precarious endgame.

“Once Brexit is behind us, you are in a different place,” the second MP says.

“Everyone accepts the last reshuffle was poorly done with the wrong people in the wrong jobs.

“That’s why as early as June they were thinking of doing another one, if they’d done it right in February they wouldn’t have needed one.”

When the reshuffle comes, it could include a major reconstitution of government departments and how Whitehall is run.

“That will tend itself to be later,” they say.

“I think it will be quite big, I think it will be reconstituted, I think that’s when the machinery of government stuff will happen.

“It will be very refocused, they will be much less bothered about the Brexiteer stuff and much more bothered about who’s good.

“Because I think they have realised they need better people.

“And that will mean it will be a bit longer.

“And then if you do that right you then have only one more big one before the election.”

No.10 was approached for comment.