Picture one, good
picture two, bad
I find picture one to be a really compelling reason to turn off the lights after you leave a room. It personifies a light switch in order to cause you too sympathize with it. It also uses an experience that most people (adult people) have experienced in their lives, and it does so in a humorous way. Humor can be a great way to get people to be more receptive to and idea or have them thinking about it longer.
The second image (sorry for the small size). Is ineffective for a couple reasons, the first being that the words take a backseat to the photo, which looks like some guy wasting water on an egg (clearly a stock photo). The second reason it doesn't work is that the image and text are fighting, fighting for our attention and focus, one is trying to convey a powerful message while the other is trying to distract us from it, the two done work together in harmony.
The success of an image is to connect with a viewer on a deeper level, to get the viewer to really think about the message, and relate it too their life. Only one of these images can truly do that. Without that connection the message soon just falls away and we are not left with any real added meaning to our lives.