Unrewarding (adjective)

1. Not having been rewarding or not having been fulfilling.
2. Not having been beneficial or not having been profitable.
3. Not having been gratifying or not having been satisfying.

Origin:

From the latin word "in-" meaning not and the past participle "rewarding" meaning rewarding or fulfilling.

Examples:

1. The job was unrewarding and he quit after a month.
2. The experience was unrewarding and not worth the effort.
3. The project was unrewarding and not successful.
4. The relationship was unrewarding and not fulfilling.
5. The task was unrewarding and not challenging.