How is the PM too powerful?

Under the Coalition, the media regularly talked about formal and informal meetings of the ‘Quad’, which consisted of the Prime Minister, Chancellor of the Exchequer, Deputy Prime Minister and Chief Secretary to the Treasury.
As key leaders of both coalition parties, they met to discuss and agree policy that would be acceptable to both parties. These meetings drew comparisons with Tony Blair’s approach of ‘sofa government’, where key decisions were made on the sofa in the Prime Minister’s office, rather than in formal, recorded cabinet meetings.
Under Cameron’s majority government it was claimed that ‘cabinet government’ was again in decline, replaced by the powerful ‘duopoly’ of Cameron and Osborne.
Despite being a cabinet member and former party leader, Iain Duncan Smith said after his 2016 resignation that policy was “changing literally by the hour”, without his, or the cabinet’s input.

Cabinet reshuffles highlight how vulnerable ministers can be if their departments are not achieving positive media coverage and public approval, or if the minister’s views conflict with the majority of the government.
In 2012, Ministers who were deemed by some to be unsuccessful or controversial, such as Andrew Lansley, who had been working on divisive reforms to the NHS as Secretary of State for Health, found themselves replaced.
Others, who held views that were in the minority, such as Secretary of State for Transport Justine Greening, who opposed a third runway at Heathrow, were also strategically moved. Upon becoming Prime Minister in July 2016, not only did Theresa May undertake a significant reshuffle, with nine of Cameron’s ministers either sacked or resigning, she also streamlined the numerous cabinet committees that carry out much of the day to day work of government.
She greatly reduced the number of committees, and decided to chair all but one personally, giving her significant influence over the direction of her Government.
Prerogative powers are exercised without the need for Parliamentary approval, making scrutiny over their use, and opposition to them, extremely difficult.
In 2015, Cameron’s authorised the use of drone strikes in Syria in spite of a parliamentary vote against military intervention in Syria just two years earlier, demonstrating the limited checks on these powers.

As the media and public often view the PM as the lead spokesperson for the Government, their popularity is indispensable to the party.
During his time as prime minister, David Cameron often performed better than his party in the polls, even when both had negative net approval ratings.
In Feb 2016, Cameron’s net approval rating was -15, but the party’s was -26.
Having led the Conservatives to their first majority since 1992, Cameron also enjoyed a short-term boost to his political power, due to the gratitude of MPs and members.
According to an Ipsos Mori poll in February 2017, May had a net approval rating of +17, compared to Labour leader Jeremy Corbyn’s -38.
This correlates with the overall popularity of the Conservative Party, which won 98 more seats in the general election.