His behavior seemed to be without 'motivation'. = There seemed to be no 'motivation' [='reason, motive'] for his behavior.
Many people have questioned her 'motivations' in choosing to run for office at this time.
a 'motivational' speech [=a speech that is intended to motivate people]
(..) Confirmed by all. Independently. I had feared the Priory's penchant for secrecy might prevail. The prospect of death is strong motivation. It is here. In Paris, Teacher. It hides beneath the Rose in Saint-Sulpice. You will go forth, Silas. (..)2006 The Da Vinci Code