Definition of "insufficiency"

She may crowd her days with gaiety, variety, and what are called amusements; she will do so only to find their insufficiency.

1837, L[etitia] E[lizabeth] L[andon], “Chapter XXI. Lady Marchmont’s Journal.”, in Ethel Churchill: Or, The Two Brides. […], volume III, London: Henry Colburn, […], page 160

On a recent trip down the Rhine many of the trains we saw were still steam-hauled, presumably through an insufficiency of electric locomotives, as yet, to deal with peak summer traffic.

1962 October, “Beyond the Channel: Western Germany: Rhine right-bank line re-signalling”, in Modern Railways, page 276