Most bathroom disasters aren’t bad luck—they’re bad decisions. The biggest mistake is prioritizing aesthetics over practicality; that’s how you end up with slippery glossy floors, no ventilation, and fixtures placed like an afterthought. Another common failure is poor lighting—soft, dim lights may look cozy but are useless for shaving or makeup. Tiny bathrooms get drowned in bulky vanities and oversized tiles because people refuse to measure properly. To avoid these problems: choose slip-resistant flooring, install proper exhaust and natural light, plan storage into the layout—not after, and match tile size to the room size. Think function first, then design.