The interior is looked at for a number of reasons. The interior provides clues to structural problems and is often the area where water leakage is first detectable. The interior finishes themselves usually reflect the overall maintenance.
The house interior contains the distribution points of the major systems. For example, each room should have an adequate heat supply and sufficient electrical outlets. The concern of the house inspector is function rather than appearance, and emphasis is placed on whether the room will work as it was intended. The home inspector does not comment on matters of personal taste.