From W. J. Slater's Lexicon to Pindar, p. VIII:
"A lexicon is the result of two opposing processes, compilation and compression. The first resembles the work of a magpie, the second demands ruthless self criticism. Therefore, even though I have often quoted Pindar at length at the price of doing justice to his commentators, on the principle Πίνδαρον ἐκ Πινδάρου σαφηνίζειν, I have nonetheless been painfully aware, brevis esse laboro, obscurus fio. Any lexicon is a compromise between these two attitudes."