Floor lamps vs ceiling lamps
A floor lamp is a consumer product sold loose with an electric cord.  It plugs into a receptacle.  It has a light switch on the lamp.  It takes up space, people knock the lamp over and trip over the cord etc.  

A ceiling lamp is built into the ceiling with special wiring in the wall and ceiling.  It is expensive to install the wiring, more expensive to buy, and you need a qualified person to install it.  It doesn't take space, nobody knocks it over or turns it off, and when you turn on a light switch, a light comes on.  

Every room must have a light switch.  Normally, this light switch operates the ceiling lamp.  However, builders got an exception made in the Electrical Code in order to make houses cheaper: they can omit the expensive ceiling lamp wiring and switch a receptacle instead.  The citizen is expected to buy a floor lamp, and plug it into the receptacle, which is always in an inconvenient location.  

The problem with this plan is that citizens often abandon the use of the light switch entirely. They switch the lamp off at the lamp.  They don't even use the receptacle and use other lamps switched at the lamp.  Only they know how to turn the lights on.  Visitors (i.e. firemen, EMTs and police) can't turn the lights on.  They fail to search the room for victims, give medical care via flashlight, and just shoot the kid holding a they-can't-see-what.