Earlier quoted context omitted.
But never forget that malice does exist, and the clever malicious will often conceal their malice behind a veil of plausible stupidity. For instance, "Oops I accidentally forgot my briefcase full of classified documents on the bus" is as old as spycraft itself.
Even calling it "clever" or attributing it to spycraft is a stretch. Kids learn to "play dumb" before they learn to form complete sentences.
"I'm sorry sir, I kicked in your front door and started looking for cash and valuables because I was drunk and thought it was my house! I made a huge mistake!"