Political parties invest great amounts of time and energy into preparing for election campaigns – far more, generally, than the media covering them. For all that we’re constantly questioning their strategic decisions, an awful lot of thought and research goes into most of them, and even if they don’t pan out there’s usually a good explanation behind them.

Still, this election has contained its share of mysteries when it comes to what the parties were thinking. Here’s a quick look at what was, to these eyes, the most baffling miscalculation by each party.

The Liberals’ debate prep

Yes, it was bad luck for Kathleen Wynne that the very first topic in her first leaders’ debate – before she’d had a chance to let her nerves settle – was the gas-plants scandal. But that still doesn’t explain why she didn’t have a better plan for the inevitable questions on that subject than to repeatedly apologize while uncomfortably staring straight ahead as the other leaders berated her, then make an awkward and unsuccessful attempt to change the channel to Tim Hudak’s math problems.

Ms. Wynne was being prepped for the debate dating back to last year, so it’s not as though no thought went into this. One theory offered by some Liberal insiders is that, somewhat in keeping with the way their party has made both political and policy decisions since Ms. Wynne took over, there were a lot of people in the room during those sessions – and enough conflicting advice that she didn’t have a clear idea of what she was supposed to do.

Another explanation also floating around is that while they expected Mr. Hudak to be tough on her, the Liberals failed to adjust to the aggressive persona Andrea Horwath had taken on by the time the debate happened. Instead, by this account, Ms. Wynne was prepared for the folksier version of the NDP Leader from the 2011 campaign, and left flummoxed by the attack from both sides.

Or maybe the prep just didn’t take as it should have, with Ms. Wynne’s nervousness getting the better of her. Whatever happened, if the Liberals lose on Thursday, they’ll have cause to look back on the debate with some regret.

The Tories’ hard sell of 100,000 job cuts

The more obvious choice for a Progressive Conservative mystery in this campaign might be how Mr. Hudak’s policy advisers managed to badly botch the math behind his pledge to create a million new jobs, causing him no shortage of embarrassment. Chalk that one up to sloppiness, albeit of the fairly remarkable variety. What’s even more confusing is how the Tories rolled out their plan to cut 100,000 jobs from the broader public sector.

When they announced that pledge, a few days in, it seemed obviously intended as something to seize the electorate’s attention and become the talk of the campaign. If it wasn’t, then surely Mr. Hudak would have soft-sold it as relying largely on attrition rather than giving the impression that it involved firing a lot of people.

But by the accounts of many within their party, the Tories were genuinely caught off guard by how much the proposed cuts overshadowed other policies they rolled out in the days that followed, and the extent to which it gave their opponents something to rally against. So in subsequent the weeks, Mr. Hudak did start talking more about attrition – but only after the other parties had reasonably been able to characterize his proposal as mass layoffs.

Prior to the debate, several PC sources have said, there was starting to be a degree of finger-pointing within their party about both the million-jobs math and the jobs-cuts roll-out. A better mood set in because of the perceived momentum swing in their favour, which seemingly had much to do with the focus shifting to Liberal scandals. But there will again be plenty of second-guessing if the motivated centre-left keeps them from office.

The NDP’s slow start

Frankly, almost the entire NDP campaign has been baffling. While there have been occasional signs of what could have worked – Ms. Horwath is a more confident performer than she was in 2011, and when anyone has actually seen them their ads have been pretty good – it remains unclear why the New Democrats forced an election for which they lacked both a policy agenda and enough money to compete with the other parties.

What is especially confusing, though, is why Ms. Horwath was so unprepared for the campaign’s first week. In the run-up to the May 2 provincial budget, neither of the other parties could be certain how the New Democrats would respond. But in retrospect, considering that their rejection of that left-leaning budget clearly had little to do with its contents, the New Democrats should have known well before it was presented what they were going to do. And if they had bluffed publicly about weighing their options while making preparations behind the scenes, they might have run the smoothest campaign out of the gate.

Instead, the New Democrats looked more surprised than anyone by the government falling. It took them the longest to get their logistics sorted out, and more important they lacked a compelling explanation for why they had decided to bring the Liberals down. This was probably the time to make the strongest possible argument about Liberal corruption, as Ms. Horwath tried to do much later; instead she stumbled through a less-than-compelling case about liking Ms. Wynne’s promises but not trusting her to deliver on them.

As a result, Ms. Horwath squandered the spotlight that was on her in those first days. Before long, with the other leaders campaigning more strongly, the narrative of a two-way race had taken hold – one the New Democrats were never able to shake in the weeks that followed.