I find this is one of the biggest appeals in being an electronic musician using hardware and may be another reason why many artists truly feel compelled to acquire so many different instruments as you are encouraged to discover new expressions through how your body interfaces with them.
I think i first truly understood this on using my first proper music machine, a Moog Voyager OS where after having been a computer musician who loved programming software synths and getting weird sounds out of them, I discovered how this Moog’s real potential lay where it was making me play those weird sounds and shape them in a intuitive/reactive/communicative manner that was not known within myself when I was in that more sound design/programming minded space of using a keyboard and mouse to navigate a virtual interface on a computer display.
Getting into the material aspects of this yes…It was my first experience of the analog synthesizer. The physicality of a relatively humongous slab of wooden analog synthesizer. The balance and presentation of its parameters, large and smooth analog potentiometers where I could sense that truly infinite resolution and encouraged me to push just how subtle a movement I get out of a given sound. And finally how this all tied into the primary interface of the piano keyboard. Even though I am not a keyboard player I really felt like wow! So THIS is the legacy of the great instrument maker Bob Moog.
And so now more than 10 years later I really think about this a lot.
Ive since realised I love experiencing how the varying interfaces of musical devices influences and shapes musical directions and outcomes.
The excitement to engage with a new musical object and discover for myself the playful possibilities of a given musical interface. There must be a great satisfaction in achieving mastery over a given interface, something I have not known although there is no way to say that with certainty
but it has been humbling when I witness a total noob who has no idea how to play something and just intuitively does it in a way that is totally their own, possibly resulting in a unique expressiveness that is come about purely due to the innocent sense of discovery involved in that early attempt.
If and how one is a able to recognise and retain that special innocent feeling and if a musical instrument can be designed(or has already been?) to give you this experience is another thing that excites me.