Peeing in the shower is extremely common and generally medically fine for healthy people in their own bathroom. It may also provide a small water-conservation benefit, but there are a few practical caveats—and a strong “ick” factor for many people.
Anatomy
The meme you shared captures a near-universal private debate. The incomplete punchline (“it means that you are…”) invites everything from “efficient,” “environmentally conscious,” and “a multitasker” to “gross,” “lazy,” or “someone who will never admit it.” Reality sits somewhere in the middle of the practical and the mildly taboo.