Seems like a better definition of “safety” would be:
- Assured admission
- Including to division or major, if applicable
- Assured affordability
When admission is non-assured, that can introduce uncertainty based on subjectively graded application aspects (evaluation of course work and extracurriculars, essays, recommendations, level of applicant’s interest). Even when there are no subjectively graded application aspects, competitively determined thresholds may vary from year to year.
Back to the OP’s situation, if IU business has assured admission and affordability, then there is no reason for the OP to apply to other schools which they would not choose over IU business.