C1 adjective /ˌɪn.ɪˈfɛk.tʃu.əl/
ineffectual
ineffektiv
Meaning
Not producing any or the desired effect; lacking the ability or qualities to achieve a purpose.
Example
The manager’s ineffectual leadership caused the team to lose motivation.
Die ineffektive Führung des Managers führte dazu, dass das Team die Motivation verlor.