HOA Homefront: Can we spend reserve funds on insurance?

Q: Last year after insurance skyrocketed, the HOA board borrowed from the reserves and then paid back the reserves with an assessment. We then learned that the board borrows from the reserves every year to pay the insurance and then pays it back over time, without notice to the residents.
My understanding is that annual insurance payments should be part of the operating budget. Is it legal for the board to borrow every year from the reserves to pay the annual insurance payment? I understood that