Voters look for leaders with; experience, decisiveness, good media image, ability to lead, honesty.
Success; May in 2016 had high poll ratings when she took over from Cameron; as former Home Secretary for 6 years she was seen as a steady pair of hands; elected unopposed by her party which demonstrated leadership qualities; good media image as tough and clever.
Failure; Corbyn in 2015; not seen as intelligent; not a unifier as Labour MPs passed a motion of confidence in him in 2016.
However, in 2017 election, May's leadership was unable to defeat Corbyn.
Unity and Party Success
Some say that a disunited party has no hope of being elected.
1980s; Conservatives united under Thatcher; Labour split between left and right wings; Labour split due to Limehouse Accords in 1981.
1997; Labour united around Blair and New Labour; Conservatives under Major split over Europe.
2016; Conservatives united over getting Brexit done however by 2017 Election they were not as united; in 2017, Labour able to unite around Corbyn's manifesto and increase seats.
The Media and Party Success
Electorate influenced by images of the party in media.
Wavering voters and good press campaigns can sway voters.
In 2017; majority of newspapers supported the Conservatives but Labour won seats - suggests that media does not change voter opinion.
In 2017; 39% of 'Sun' readers voted Conservative; 50% of Guardian readers voted Labour.
Broadcasters and TV debates must be neutral; Lib Dem Nick Clegg performance in 2010 allowed them to enter coalition however they actually lost seats at the election so arguably little impact; recent years have seen leaders absent.