the no alternative years

Labour  failed in the most basic ways. They had four years to develop a counternarrative, but instead developed a counter-excuse: "we were so austerian, as austerian as you!" Basically, if you can't capitalize on the reserve of good feeling for government agencies like National Health and the reserve of bad feelings for privatized agencies, like the train system (ooops, that dittoed under Blair), then you should not play ball.
There are good defeats and bad defeats. A good defeat is one that lays the ideological groundwork for the future. A bad defeat is one that leaves behind a wreckage of opportunism and users. The Labour defeat (why actually are they still called Labour?) is of the second variety. It was hard to care when, as was obvious months ago, they had succeeded in turning certain victory into defeat. Running on a blairite message of nudgery and sticking to austerity against a tory party that was also running on a blairite message, they lost lost lost. And then, too, there was the repulsive - to my mind - Milliband, who has the look and feel of an upper class jerk.
So why didn’t Labour hammer austerity? Well, you have to talk about why the Great Slump happened if you are truly going to hammer austerity. And that means you have to talk about the City - which were and are great friends of the Blairites. There is a stupid analytic habit of thinking of elections as separate events from the rest of the political flow. They aren't. By choosing to softpedal the problems caused by the City, Labour backed itself into a corner long ago. Plus, of course, they have to bear the burden of the insane and wicked foreign policy of the Blair years. Given these burdens, one had to mark Labour down as the underdog from the beginning. The excuse that it was mean old Murdochian media that put them down won't work - Labour's victories have traditionally come against the establishment press – the one exception being Blair, and we know the sacrifices that Blair’s endorsement imposed. To face that media attack requires being nurturing of a structure that can withstand it and attack back - organized labour – to create a counternarrative. Blair (whose victories were a disaster for Labour) carefully cut the tie to labour. While Ed Balls retreat on austerity was bad in the campaign, it was the symptom of a wholesale disintegration of the old labour structure. 
A good case in point is transportation. Have you ever ridden on a London bus or a british train? They are awful and much, much more expensive than theircounterparts on the continent.
But the thatcherism that Blair adopted and passed on to his successors disallows any discussion of the issue of privatisation - which was accomplished, in the UK, after the Thatcher government thoroughly trashed the service and maintenance of the nationalized train system. A simple populist program that would call for comparable pricing to the norm in the EU would actually have put money in the pockets of the wage class. But it would have offended the city, and the blairites, and so it can't even be spoken. Instead, the pledge was a process one of handing power over buses back to regional authorities and blah blah blah. It was typical of the thrd way style: a lot of boring process talk to get around offending the moneyed. 
I think this election is a premonitory of the next pseudo-left wipeout, in France. The PS has set itself up for one of those defeats it will be hard to survive. Unfortunately, we will have a rightwing Europe to contend with in the next decade. Unfortunately, too, it won’t look much different than if we had a pseudo-left Europe to contend with in the next decade. No alternative, once a slogan, is now a cancer.