Went back and read it again, I think it's the phrase "bonus reducer" that seems confusing. It's not actually reducing your bonus to complete opportunities, in fact it actually IS a bonus to complete them.
This is totally just a suggestion, but you could rewrite it like this:
Career Opportunities: For each opportunity you complete it will give you a bonus of subtracting .25 days from your time. So the more career opportunities you complete, the faster your time will be.