Fortunately most house plants and people are comfortable at the same temperatures. However, houses are not at a uniform temperature throughout. Some rooms are cooler or warmer. Even within a room, some areas are cooler or warmer than the rest of the room. Temperature affects plants in several ways.
Some plants require a drop in night temperature to bloom.
If a plant is given all the factors needed for maximum growth, but the temperature is too cool, the plant will grow more slowly than it could. Most plants will not adapt to rapid temperature fluctuations as can occur near a doorway in the winter. Each time the door is opened, nearby plants get a blast of cold air. The same is true of a plant growing near a furnace vent or a heat generating appliance. Drafts which are too warm or too cold can cause drop of leaves, flowers or flower buds.