Substandard Magic Items (5E)

From publisher blurb:

This supplement takes the concept of scroll mishaps and applies it to magic items in general. Scroll mishaps occur when a user tries to cast a spell scroll beyond his current ability (i.e. when his reach exceeds his grasp, although the opportunity is there for success). Substandard magic items come at this from the other direction – competent spellcasters use shortcuts and inferior components to arrive at a cheaper, yet fallible, magic item. These casters have the ability to create a normal item yet they either can not or intentionally choose not to.