The centrality of the clock to the emergence and organisation of capitalist exploitation has long been discussed.  Lewis Mumford wrote (1934),  "the "clock, not the steam-engine, is the key-machine of the modern industrial age."  From Technics and Civilization.   George Woodcock (1944):  "Socially the clock had a more radical influence than any other machine, in that it was the means by which the regularisation and regimentation of life necessary for an exploiting system of industry could best be attained. [...] Time as duration became disregarded, and men began to talk and think always of 'lengths' of time, just as if they were talking of lengths of calico. And time, being now measurable in mathematical symbols, became regarded as a commodity that could be bought and sold in the same way as any other commodity."  The rest of "The Tyranny of the Clock" here.

Yet there are also questions that might be worth raising about the spread from public clocks to workplace clocks to personal timepieces (and beyond this, perhaps, the shift from clockdials to digital readouts. )

Martin Heidegger wrote: "Looking at the clock is grounded in and guided by a taking-time-for-oneself … Looking at the clock and orienting oneself toward time is essentially a now-saying. Here the now is always already understood and interpreted in its complete structural content of datability, spannedness, publicness, and worldliness" [ From Being and Time. ] 

Combining this particular insight about the socialising (worlding) action of looking at one's watch -- or checking the time -- with a sense of the rise of and transformations to Taylorism, it is possible to note the centrality of the personal timepiece to the rise of self-managed, individuated but nevertheless programmable and co-ordinated (diffused) exploitation.   Moreover, whereas clockdials resonate -- however nostalgically -- with cyclical concepts of time, digital readouts amplify the sequential and linear senses of time, 'making the seconds countable' like never before.