Every night, all around the country, in the 21st century factories known as call centres, some 750,000 workers will breathe a collective sigh of relief as they get the signal that their shift has finally come to an end.
The signal to stop work in the call centre I work in is a manager flicking the main switch off and on - "flashing the lights".
It's a moment of glee as workers are released from the monotony of repeating themselves for hours and the stress of attempting to convince someone to part with a slice of their wages or pension. At that moment, we can all relax. Or perhaps not.