Because we don't have the skills. The necessary tasks are becoming more skilled, not less, as society progresses. That's what defeats the old 'socially necessa

Because we don't have the skills. The necessary tasks are becoming more skilled, not less, as society progresses. That's what defeats the old 'socially necessary labour' concept. Essentially few of us are good enough to do the jobs that need to be done, nor can we become good enough because we just don't have the talent.