It would be a different number of times for each career level. As your lil peep progresses in their career, each level takes longer to complete. For example, Levels 6 and 7 take many more cycles than levels 1 and 2.
It would also be very difficult to calculate exactly how many cycles because we are not provided with an exact measurement on the progress bar and our lil peeps complete work cycles when the game is closed.
You can upgrade their workroom/s to help out with progress when it feels like it is going super slow. Other than that, continue to praise them, purchase professional magazines for their appropriate career/s and use candies to praise when they are available in the store.
Hope that helps.
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