Ones opinions on the attributes or flaws of the two leaders notwithstanding, the fact is that they were each elected into their positions at difficult times and, not having been able to demonstrate convincing leadership, remain weak - which, imv, accounts for their inflexibility and inability to negotiate.
From the, pretty much expected, inconclusive results of the indicative votes it seems clear that if we are to leave with the deal rather than no-deal, Labour will have to vote for it. May should be (or have been) negotiating with Corbyn not her no-eyelids right wing.
Maybe she can still do this, one step removed, by putting Ken Clarke or Hammond in charge of organising such a deal.