Skeuomorphism in practice

Mechanical watches have been around since 1500s, mass-produced since the 1850s. At that time, functionally the mechanical design of the watch made the use of hour and minute hands a necessity.

Above: The Pebble smartwatch

Image Credit: Devindra Hardawar/VentureBeat

The first electronic/quartz watches appeared in the early 1970s, more or less simultaneous to the advent of display technologies. Almost overnight, watches with hands were nowhere to be found, and the numerical “digital” display became the standard. People could tell time to the split-second and believed that their speed to read the time was improved.
But today, digital watches are almost a thing of the past.
If a wristwatch is worn today, an analog display is standard — particularly for upscale watches — and could easily be mistaken for the mechanical watch of 50 or 500 years ago. Once the thrill of innovation subsided, users found that the need to tell time to the split-second was less important than the ability to quickly mentally process the approximate time of day using the analog dials on the watch.
What they discovered was that reading the numerical display took longer for the individual to process in terms of the amount of time left in an hour.
Digital displays are still used in places where precise accuracy maters, but when speed matters and approximate assessment of time is enough, hands on a clock face are more efficient. For example, aircraft cockpit designers have found that it may take longer for a pilot to process numerical versus analog gauges — so even though in an aircraft these split seconds can matter, the analog (skeuomorphic) approach has remained on many gauges.
A similar functional skeuomorphic example could be found in a car.
If a driver has information on a fuel gauge indicated 2.69 gallons remaining, he/she may get bogged down by mentally having to compute the miles per gallon, make an assessment of the length of the drive, and then make a decision to go and get gas. With fuel gauge that simply shows “Full” and “Empty,” the driver could look at the gauge pointing towards E and immediately start to think about where to refuel.
 FROM:
http://venturebeat.com/2013/09/11/ios-7-windows-8-and-flat-design-in-defense-of-skeuomorphism/