Life is serious business. Every action has its consequence. If G-d didn't judge us then there would be no justice in the world. From our perspective, if we feel that we are being judged, we are more likely to treat life seriously. We will then hopefully correct our mistakes in dealing with other people, ourselves and with the Almighty.
Judgment implies caring.
If you don't care, you don't judge. We look at G-d's judging us as the ultimate expression of His love and caring about how we live our lives. There is an often told story of a man who hears on the radio a report of rising flood waters. The police come to evacuate him. As the waters rise and threaten his home, along comes a boat with an offer to take him to safety.