"I don’t think we can discount pure pretension and misplaced self belief driving certain characters forward."
Agreed. If you are the type to want to lead a political party (particularly this one, at this stage) then ego has to play a massive part.
If you aren't sure that you will retain your seat (eg Schapps & Mordaunt) then it must make sense to make your move before the election. Ideally after a trouncing on May 2nd.
And then hope that you get a bounce in the polls & can then steer them to loosing less than the worst predictions so you can hang on beyond the election.
Obviously by that point you'll be spending the majority of your time fending off competitors.
And of course this all requires you to have zero understanding of how fucking ridiculous your party looks to everyone else.