It is a labour intensive process requiring significant laboratory resource over a number of years, limiting drug companies' willingness to invest.

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With most of the work done by hand without any help from modern technology, its production is a lengthy and labour-intensive process.

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Much of the work cutting and printing laminates that make the shell of the ball was done in factories, but stitching, the most labour-intensive process, was usually outsourced to families in villages around Sialkot.

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Even though the climate is suitable, tea-growing is simply too costly, since the process is labour-intensive and resists automation.

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