copout

Avoidance or inadequate performance of a task or duty; the action of copping out.

“His disappearance on the day of the audition was just a cop-out.”

An excuse made in order to avoid performing a task or duty; a reason offered when someone cops out.

“It was a cop-out to say he couldn't sign the petition because he sprained his wrist.”

A person who cops out.

“He's always a cop-out when there's hard work to be done.”