inerrable (adjective) infallible: unerring, dependable
Sinonime: can't hack it, careless, disorganized, extravagant, faulty, feeble, half-baked, improficient, improvident, inapt, incapable, incompetent, ineffective, ineffectual, inefficacious, inept, inexpert, not cut out for, prodigal, shooting blanks, slack, slipshod, sloppy*, slovenly, unfit, unprepared, unqualified, unskilled, unskillful, untrained, weak
Antonime: erring, fallible,
faulty,
imperfect