Unrealised
Part of speech: adjective
Definition: Not realized; possible to obtain or achieve, yet not obtained or achieved.
Unsuccessful
Part of speech: adjective
Definition: Failed, not successful.
Example sentence: Our physiological constitution is obviously a product of Darwinian processes, insofar as you buy the evolutional theory as a generative, as an account of the mechanism that generated us. Our physiology evolved, our behaviors evolved, and our accounts of those behaviors, both successful and unsuccessful, evolved.