No. That habit belongs to nickel-cadmium cells, which modern grooming tools do not use — and on a lithium cell running it flat repeatedly is the one thing that actually shortens its life.
The practice came from a real problem that no longer exists. Nickel-cadmium cells suffered a memory effect: charged repeatedly from half, they behaved as though half was empty, and a full discharge reset them. Lithium-ion cells have no memory effect, and the advice survived the chemistry it was written for.
What is true of a lithium cell is close to the reverse. Deep discharges are the hardest thing you can do to one, and a cell held between a quarter and three-quarters full ages more slowly than one repeatedly emptied. Topping up after every use is not a bad habit — a top-up is only a fraction of a cycle, and the cell spends less time near empty.
What the catalog actually publishes. Nothing on this site states a discharge requirement. One product states a first-charge instruction — the Xoomrscp nose trimmer, whose own listing opens with “Fully charge your device before operation”, and it is the only one of the 137 to say it. Several publish a full charge time, which is a different thing: the Remington MB5000 publishes two hours, and that is how long a charge takes rather than an instruction about the first one.
So the one instruction worth following is the one that is published, and it is about storage rather than charging: do not leave the tool flat for months. If a trimmer is going in a drawer until next summer, put it away part-charged.
Check your own manual before you follow anything here. Temperatures, water ratings and supply voltages differ from model to model, and the maker’s own figures take precedence over anything written on this site. A supply of the wrong voltage is a failure rather than a slow charge, and the figure is printed on the tool — not inferred from a connector that happens to fit.
Last reviewed October 10, 2026