I've thought for some time now that corporate inflexibility was part of the cause. More of us work for large, bureaucratic companies than in the past. These sorts of companies often won't employ someone on a flexible or part-time schedule because it would be too complicated to manage. It's actually easier and cheaper to let you site at your desk and waste time for 10-20 hours a week than it would be to figure out and manage an alternative. Do you think this rings true in the UK? It certainly does (in my experience and observation) in the US, though I think in the US healthcare is at least as important a factor.