unprofessional (adjective)

1. The historian found the unprofessional behavior of the king during the Battle of Hastings to be inappropriate and lacking in dignity.

2. The designer was criticized for using unprofessional materials in their couture collection, resulting in a poorly constructed garment.

3. The priest was reprimanded by the bishop for his unprofessional conduct during the church service, causing a disturbance among the congregation.

4. The horror movie director received negative reviews for the unprofessional use of cheap special effects, diminishing the terrifying impact of the film.