‘To me, a fixed election date is something that we should actually set and stick to’: Dennis King in 2019
The short answer is, because Dennis King wants one now.
Since Confederation it has been the prerogative of premiers and prime ministers to call elections when they deemed it was time to do so. This frequently led to cries of foul, when leaders moved to call elections when they appeared to have an advantage, or delayed calls to avoid what seemed to be certain defeat.