Some time ago a reviewer remarked "I am also wondering whether results about all kinds of Lie algebras are what we should be looking for. This is what you do at the earlier stages of a theory, may be to see how far the defining axioms can take you. If I am not mistaken, people nowadays look for structures that appear in some context." Whilst I understand the importance of motivation in mathematical research, I'm puzzled by the fact that results claiming to elucidate the structure of important classes of Lie algebras, such as solvable or nilpotent algebras, require further justification. Has the context here not already been established?