With no second story, exterior repairs (like gutter cleaning or painting) are simpler and often cheaper.
The single-floor layout eliminates stairs, making it ideal for aging in place or for those with mobility issues.
All rooms, including bedrooms and bathrooms, are on the ground floor, which can make them easier to see into from the street.
Because they require more land and roofing per unit of living space, you typically pay a premium compared to a house.