Descaling is non-negotiable
Hard water leaves mineral deposits inside your coffee maker, and those deposits do two things: they slow the machine down and they dull the flavor of every brew. Descaling dissolves that buildup and should be part of a regular routine — roughly every one to three months depending on your water.
Use the descaling method your machine's manufacturer recommends. The process is usually simple: run a descaling solution through a brew cycle, then run plain water through twice to rinse.
The daily habits that matter
Rinse the carafe and filter basket after each use, and leave the reservoir lid open so it can dry between brews. Wet, closed reservoirs are where odors and residue start. A dry machine is a clean machine.
Replace disposable filters on schedule, and if your machine uses a reusable filter, rinse it thoroughly — old grounds go stale and bitter, and they taint the next pot.
When to consider replacing it
Coffee makers are consumable appliances, not heirlooms. If descaling no longer restores performance, the machine drips slowly, or the warming plate stops holding temperature, the cost of repair usually exceeds the value of the machine. A well-maintained budget brewer can last for years; a neglected premium one will not.