What does short or over budget mean?

Short means you are under your planned budget. Over means you have exceeded your planned budget. If your budget was planned correctly, the best place to be is as close to your budget as possible. If you are under budget too much, you might not be spending where you should to grow or protect your business. If you constantly are over budget, then you may be in danger of going out of business, because of lack of money to spend on the things you need to stay in business.