Again, the science is inconclusive but there are two major theories. One school of thought maintains that we feel more relaxed and comfortable in the shower, not to mention that we’re typically alone. This physical comfort gives way to mental comfort, and before you know it, you're belting out Taylor Swift (don't lie). The other theory is that the tile, plastic, glass or ceramic that lines your bathroom creates an acoustically-pleasing environment. This makes your voice sound fuller, and helps hide imperfections in tone and pitch, thus releasing your inner opera star.