A washing machine that leaks water is almost always one of a small number of failure points, and where the water appears tells you which.
Water at the back of the machine: inspect the fill hoses where they connect to the wall valves and to the back of the washer. Rubber fill hoses are a top failure point and the one residential-plumbing failure most likely to flood a laundry room — per insurance-industry data, hundreds of millions of dollars in annual U.S. property claims come from burst fill hoses. Replace with braided stainless-steel hoses every five to seven years regardless of visible condition.
Water under the front of a front-loader, during the wash cycle: the door-boot seal (the rubber bellows around the door) has torn or has debris trapped in a fold. Bleach and detergent residue eventually hardens the rubber until it cracks. Boot-seal replacement is a moderate repair at $250 to $400 on most front-loaders.
Water under the machine mid-cycle, regardless of front or top load: the drain pump, a drain-hose connection, or the tub seal. A tub-seal failure (the seal between the transmission and the inner tub) usually also produces loud bearing noise during spin and typically argues for replacement over repair on older units.
Before calling service, check the obvious: overfilled with high-efficiency detergent, over-sudsing, or a load too large for the drum.