This is something that has bothered me for quite a while. I frequently participate in instrument demonstrations for children. My focus is on wind instruments but I'm also curious about others.
What I noticed is that some children just seem to have a strong affinity to certain instruments. And some seem to be absolutely unable to produce sound on some instruments. I noticed that there are children who just naturally place their lips right on the instrument and others who seem to be physically unable to hold their lips in those positions (think someone who can't roll their tongue but desperately tries to). There are children who blow in a strong and narrow fashion and others who tend to blow much broader, some have a strong grip with their mouth, others a more soft one. Finger length and lung capacity are also important of course but in children this is hard to factor in since they are not developed enough. And then there are obvious genetic malformations like missing fingers that of course can severely limit the amount of instruments you can play, but I'm more interested in the not-so-obvious ones.
You see I started thinking that maybe some people just simply don't fit certain instruments and will never do as well on them as others.
So my question is, are there lesser-visible genetic limitations (lip/mouth muscles/lung capacity/blowing capabilities...) that can prevent someone from learning certain instruments? Or can those mostly be compensated by practising?