Recklessness was deliberate lack of concern for the consequences of one's actions.
while talking with Captain James T. Kirk about the Excalbians, Abraham Lincoln said to him, "We must first convince them that they have provoked us to recklessness. James, I do not mean to presume upon your authority. What I propose is that I circle around to their rear while you two provide a frontal assault. It should be sufficiently violent to cover whatever I do." (TOS: "The Savage Curtain")