Hi Lisa, and thank you for your question. It's a good one.
MPR means Minimum Property Requirements. They generally refer to concerns about safety, security, and soundness. The VA does not want to back a home that cannot be safely lived in. It's the VA insuring the loan if the house falls down, and the VA that has to pay off the lender if the borrower fails to do so.
Few homeowners are likely to continue making mortgage payments for a house they can't live in. But your safety matters to the VA, and MPR requirements protect you as well.