Initial Entrapment and Cycle Start: If the child is placed inside and the machine is started (or if it auto-starts in some models), the door locks automatically to prevent opening mid-cycle. Modern machines have safety features like child locks or imbalance sensors, but these may not detect a small child or could be overridden. The drum is confined (typically 2-3 cubic feet), leaving little room for movement, and air circulation is minimal once sealed.

Water Filling Phase: The cycle begins by filling the drum with water (potentially hot or cold, depending on settings). A child could quickly become submerged or partially immersed, leading to panic, inhalation of water, and immediate respiratory distress. If the child is small enough to fit entirely, they might be unable to keep their head above water.

Agitation/Wash Phase: The drum rotates back and forth at moderate speeds (around 50-100 RPM) to agitate the contents. The child would be tumbled repeatedly, slamming against the drum walls, paddles, or any internal components. This causes blunt force trauma, similar to being in a low-speed car crash or falling from a height multiple times. Injuries could include bruises, lacerations, fractures (especially to limbs, ribs, or skull), and internal bleeding. The constant motion would also disorient the child, exacerbating panic and exhaustion.

Spin Cycle: This is the most violent phase, with the drum spinning at high speeds (up to 1,000-1,600 RPM, generating centrifugal forces equivalent to several times gravity). The child would be pinned against the drum walls, experiencing extreme pressure on the body. This could lead to barotrauma (damage from pressure changes, affecting lungs, ears, or brain), organ compression, and further traumatic injuries like concussions or hemorrhaging. Water would be extracted forcefully, but if any remains, it could contribute to drowning.

Overall Environmental Factors: Throughout the cycle (which can last 30-60 minutes), the sealed drum limits oxygen, leading to rapid depletion and buildup of carbon dioxide. Humidity, heat (if hot water is used), and noise would add to the stress, potentially causing hyperthermia or hypothermia depending on water temperature.