inadequate

Entry Definition
(rope, wire, etc.) s/he cannot take the strain, cannot carry intended amperage; s/he cannot be coiled or arranged (e.g., too springy or stiff)
s/he rubs h/ off (soft substance); s/he wipes h/ off quickly and inadequately
it is inadequate or deficient; it is not up to snuff (e.g., trousers without a crease)