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
(c) 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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