They perpetuate the idea that there is a shortage of plumbers. Sure there was during the boom years before the recession but that was only because of the building boom. Since then building work has slowed right down and with the recession much has actually stopped altogether. With the number of new entries the labour market in many of the trades is over saturated and established plumbers are finding it difficult to fill the days with jobs. I certainly couldn't consider taking on an apprentice as there's barely enough work to sustain me and most of it's oil anyway as opposed to wet systems.