There is no optimal time for restoring wall painting, the decision being more about your desire to change the look of your house. And painting is probably the cheapest way to refresh the aspect of a room.

However, there are practical reasons why some rooms should be painted more often.

Kitchen, bathroom and laundry room

These are very popular rooms, so you have to use durable, quality paints that allow frequent wall washing without them getting a dull, unpleasant appearance. In the bathroom and laundry room, where moisture is the biggest enemy of the walls, it is recommended to use water-based paints.

In these rooms, the painting should be redone at 3-5 years. You can reduce it to some extent, if you provide good ventilation.

Hallways

The walls of the halls are very exposed to dirt and scratches, and many people paint them more often than other areas, which generally means every 2-3 years.

The living room

Even if it is a room with a lot of activity, here the wall paint stays in good condition for a longer time, because the activities are more formal. There is no need to redo the painting more often than 5 years.  Painting is the best way to add a quick quality update, see https://boext.com/.