I like to think that musicians and engineers belong to completely different groups of people where the majority of each group lacks the ability to pursue that of the other group; like a musician would find it difficult to go into engineering because of a lack in mathematic ability (or something along those lines) and a engineer would find music difficult because of the particular set of abilities it requires.

One thing though is that the barriers of entry into each category is different, music requires a lot more time and devotion and going on to make money can be more difficult because you aren't hired just by the fact that you have a bachelors concentrating in music.