> Somebody who is self taught is _by design_ somebody who's extremely motivated and interested in the subject.
How so? I've self-taught myself plenty of things that I don't have an interest in. I dare say I even despised some of it.
It seems fair to say that motivation is necessary, however often the only motivation is a means to an end, not the endeavour into the subject itself. But motivation is always necessary. That is not limited to self-teaching. I am not sure that bit is actually additive.