Update outdated `low_processor_usage_mode` doc

doc/classes/ProjectSettings.xml

@@ -344,7 +344,7 @@
 			This setting can be overridden using the [code]--frame-delay <ms;>[/code] command line argument.
 		</member>
 		<member name="application/run/low_processor_mode" type="bool" setter="" getter="" default="false">
-			If [code]true[/code], enables low-processor usage mode. The screen is not redrawn if nothing changes visually. This is meant for writing applications and editors, but is pretty useless (and can hurt performance) in most games.
+			If [code]true[/code], enables low-processor usage mode. When enabled, the engine takes longer to redraw, but only redraws the screen if necessary. This may lower power consumption, and is intended for editors or mobile applications. For most games, because the screen needs to be redrawn every frame, it is recommended to keep this setting disabled.
 		</member>
 		<member name="application/run/low_processor_mode_sleep_usec" type="int" setter="" getter="" default="6900">
 			Amount of sleeping between frames when the low-processor usage mode is enabled (in microseconds). Higher values will result in lower CPU usage.