haphazard

Haphazard means done with no plan or order. Things put wherever there was room.

It describes arrangements and methods rather than results, so a haphazard collection has grown by accident and a haphazard approach will miss things. It is a mild criticism, suggesting carelessness rather than incompetence. The word is built from hap, an old word for chance, which also gives English happen, happy and perhaps. The adverb haphazardly usually follows a verb like stacked or arranged.