This meme is funny or clever because it compares the complexity and unfamiliarity of using someone else's shower controls to a Rubik's Cube. The Rubik's Cube is known for being a complex puzzle, and many people find it challenging to work out how to get the desired water temperature and pressure in a shower they're not used to. The humor lies in the relatability of the situation and the exaggeration of the shower controls being as difficult to figure out as a Rubik's Cube.