If the car has been idle for a day or more, some warm would help. It will help the essential lubricating oil from the oil slump to circulate to protect the engine. About a minute in warm weather and in cold winter start-up it may take a up to four minutes.
The older the car to longer the warm up. Do not over-rev the engine during warm-up, just moderate rpms. During warm-up it must be in park or neutral. In in manual transmission it should be neutral. Such warm-up will reduce your engine wear and it will last longer. An warm engine does not need warm-up when started again.