Desultory is an adjective that means lacking a definite plan.

The Latin word desultorius (des ool TOR ee oos) means ‘superficial.’ When the word evolved into English, its meaning evolved as well. More recently the word is often used as an antonym of unfocused.

At best, the actress’s performance came across as desultory. But if she’d had more focus, she could have turned in fine work.