The steam wand is too weak to texture milk
Steam comes out but the milk warms without ever forming a whirlpool, or the machine runs out of steam part-way through a jug.
Applies to: Espresso machine, Cappuccino, Latte, Flat white
Safety note
Steam is hotter than boiling water. Purge into the drip tray away from yourself, and never attempt to clear a tip on a machine that is switched on or still pressurised.
Likely causes and adjustments
Try one adjustment at a time so you know what actually changed the result. Start with the first cause below — if it doesn't help, reveal the next.
Cause 1 of 5 · Commonly the cause
A thermoblock or small single-boiler machine with limited steam capacity
Is the machine ready to brew within about a minute of switching on?
An equipment limitation rather than a fault. Steam a smaller volume of milk, wait for the machine to reach full steam temperature before starting, and expect to work more slowly than a video shot on a larger machine.