David Cameron’s cynical attack on ‘skivers’ will hurt the strivers as well | Tom Clark

Those in work are finding their pay and conditions squeezed because employers know they can be replaced

During the recession, John McArthur put himself forward to work for LAMH Recycle Ltd in Motherwell, a social enterprise that reconditions computers. An electronics specialist, McArthur, now 59, had previously worked on factory floors, then retrained, moved into product development, and even started his own company. But like many in Lanarkshire, he found that a rich CV counted for little when facing a slump. Frustrated by unemployment, he seized on the chance "to sit at the end of line" at LAMH, "doing the final quality check, signing things off as good to go. It was minimum-wage work," he tells me, "but I was more than happy to do it. I had experience to share."

John was prepared for the fact that this placement, which was backed by a Labour government programme, would not last forever: it ended in 2011. Nothing, however, could prepare him for what happened next. Last summer, under a new coalition make-work scheme, he was informed that there was, once again, a post for him at LAMH. But the new "offer" came with a twist: this time John would be working without a wage. There would be no reward for 30 hours graft, only the threat of subsistence-level benefits being withdrawn if it wasn't done.

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The creep of zero-hour working continues, and there are still twice as many unwilling part-timers as before the slump