Well if you are a Tory supporter nothing went wrong; indeed you must be cock-a-hoop given that you have a Tory government when 64% of the voters wanted something else! But if you are against the Tories, you have to be wondering what went wrong.
The most obvious problem is the broken medieval electoral system we have. For practical reasons it made sense in the days of horse-drawn carts to ask each area to appoint a representative in parliament. But today we should be able to design an electoral system where MPs represent people not places, and where everybody can say their vote helped appoint someone to parliament.
As an example if all the votes for the Green party were distributed amongst the smallest UK consituencies (you did realise they are different sizes didn't you?), they would have ended up with 23 MPs instead of just 1! The Tories would end up with 240 seats rather than 331, which basically means that the Tories are very good at distributing their supporters.
In my case, my vote went towards a loser which means I'm "represented" by a politician whose policies and attitudes I find totally repulsive. There is nobody in parliament that I voted for. And the same applies to a huge swathe of the population who are now feeling alienated by the whole process.
And that is something that can and should be changed.
The alienation caused by the first past the post system is probably one of the causes of the low turnout; what is the point in voting if you live in a "safe" seat?
The most obvious difference in this election is the wholesale take-over of Scotland by the SNP, which surprised everyone. Which leads the new Tory government to a bit of a problem – with just one MP in Scotland, they essentially have no mandate to govern Scotland.
And even in England, the Tory majority is nothing to crow about – a majority of 5 is what would have been called a "fragile majority" in the past. A Tory leader with such a slim majorty is likely to run into problems if they try and ram through a radical programme.
The Tories managed to persuade many of us that a bit more self-flagellation is necessary, and punishing the poor and unfortunate is good for the country.
The effect on the Liberal Democrats is both surprising and entirely predictable. Joining a coalition with the Tories was always a mistake in terms of future elections – it was always seen as helping to put the Tories into power, and many Liberals were far less accepting of this than they would have been to see the party join a coalition with Labour. What the Liberal Democrats failed to sell was the idea that their presence in government helped to amerliorate the Tory extremes.
Labour's failure was probably down to several things :-
The failure to demolish the myth of Labour's economic incompetance that "caused" the recession. It was the global failure of the banking system that caused that failure. Labour's spending was actually reasonably restrained until the need to rescue the banks arose.
The failure to come up with a true alternative to the austerity plan of the Tories. Given the level of government debt that would be a hard job, but it could be started by pointing out (quite rightly) that simplistic austerity makes the debt problem worse.
The inability to persuade that most voters are actually "working class". There is a historic problem with the class system by which people think of the working class as cloth-capped horned handed manual workers of one kind or another. In reality, everybody who works for a living is working class.
Of course whinging about it is not going to change things. We have five years of Tory mismanagement and punishing austerity to accept now.