This means the projects should be as UN-mechanized as possible. People leaning on shovels instead of using earth-moving machinery. The idea that using manual labor instead of machinery creates jobs goes all the way back to the Roman Empire if not earlier.
as someone has pointed out, using seven workers to do a job that one worker with a machine could do doesn't create seven jobs, it splits a paycheck seven ways.
“it splits a paycheck seven ways”
The essence of socialism.