Shinzo Abe … humility

Those words don’t go together at all… unless you add a “no” before humility. ‘Poor health’ was an excuse given to cover for him breaking his promise to never resign, and he resigned because of the unpopularity of himself and the party scandals at the time. Wikipedia has a good summary:

Abe’s ruling Liberal Democratic Party suffered great losses in the upper house election, losing control for the first time in 52 years. Agricultural minister, Norihiko Akagi, involved in a political funding scandal, resigned after the election. Additionally, Abe’s rejection of a possible female Japanese monarch, which led to the Japanese succession controversy, diminished his support base.[47][48] In an attempt to revive his administration, Abe announced a new cabinet in August 2007. Support for Abe rose by 10 percent as a result; however, the new agricultural minister Takehiko Endo, involved in a finance scandal, resigned only seven days later.[49]

On 12 September 2007, only three days after a new parliamentary session had begun, Abe announced his intention to resign his position as prime minister at an unscheduled press conference.[50][51] The announcement came just minutes before opposition leaders were scheduled to question him in Parliament and shocked many. Abe had described himself as a “politician who fights” and previously pledged not to resign.[52] Abe explained that his unpopularity was hindering the passage of an anti-terrorism law, involving among other things Japan’s continued military presence in Afghanistan. Party officials also said the embattled prime minister was suffering from poor health.