It's the flickering that gets to him. He's pretty sure that his eyesight is fine - he can always spot out a mark without trying - so that flickering is annoying him. He reckons - he thinks - he might be being followed. Not exactly the best thing for one in his line of work.

So he slows down, meanders along the paths and looking in windows. Just make it seem like he's a kid who has to spend time outside till someone's back at home.