ETYM Pref. in- not + effective: cf. French ineffectif.
1. Lacking in power or forcefulness; SYN. ineffectual, unable.
2. Lacking the ability or skill to perform effectively; inadequate; SYN. inefficient.
3. Not producing an intended effect; SYN. uneffective, ineffectual.

Not sufficient to produce a desired result;

Not producing desired results; wasteful.

1. Not appropriate to the purpose; SYN. unwise.
2. Not suitable or advisable;