why 'less' (vs the real 'less') and not cat to show text

[luffah]

On most linux system, ' less ' force the user to learn its system before to be able to use it completely.
In fact, when ' less ' is running, there is no explicit indication of the commands (arrows, 'q' , '/'...).
Too, you can't leave without pressing a command ( 'q' ). In the game, ' less ' works in the same way than ' cat '.
I remember when i was a beginner with linux : it take me some minutes to find how to leave 'less' because it is pretty like 'vi' in usage; and it take me some years to consider the power of ' less '.

It is probably a deliberate choice. But why ?