Implicit vs. explicit rests
Implicit rests are automatically shown around the notes you input, and their duration automatically follows the time signature and their position in the bar. Explicit rests are rests that are explicitly entered during note input by forcing their duration, or rests that were imported from a MusicXML file.
Dorico notates implicit rests according to the current time signature, for example, different implicit rests are shown in 6/8 compared to 4/4. This also applies if you later change the time signature for existing notes and rests.
Therefore, it is not necessary to input rests in Dorico, as implicit rests are automatically shown around the notes that you input. You can turn implicit rests into explicit rests by forcing their duration to be fixed.
Explicit rests cannot be suppressed when using the Starts voice and Ends voice properties to hide rests before the first note in voices and after the last note in voices.
You can show rest colors to see which rests are implicit and which are explicit in your project.