Meaning of "real driver"

Business English Lesson, Advanced Level

ESL/EFL Test #165 [color=blue]“Commercial Property”, question 3

While the technical issues are important, the real driver should be improving for users of financial statements.

(a) opacity
(b) redundancy
© translucency
(d) transparency

Business English Lesson, Advanced Level

ESL/EFL Test #165 [color=blue]“Commercial Property”, answer 3

While the technical issues are important, the real driver should be improving transparency for users of financial statements.

Correct answer: (d) transparency

Your answer was: [color=green]correct
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Hi, I wonder what "the real driver " is here

Thanks
FangFang

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Driver in biz-speak = impetus. Also: ‘An aspect of a business that effects a change on another aspect of the business. A driver is most commonly a factor that contributes to the growth of a particular business.’
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