What are the advantages of a manual coffee grinder over a electric grinder?

Grind without heat to maintain coffee flavour

Compared to electric grinders, manual coffee grinder do not generate much heat because the speed is not very high, so the flavour of the ground coffee is less affected. Most electric grinders, on the other hand, grind at high speeds, and the friction of high speeds can cause the temperature of the ground coffee to rise slightly for a short period of time, which may change the flavour of the coffee.

Small and inexpensive, easy to carry

For those who don’t have the space or budget, a manual coffee grinder is both smaller and cheaper than an electric grinder.
Like electric grinders, they come in all shapes and sizes, but even the more advanced ones are considerably cheaper than their electric counterparts and take up less space.

Low noise Ideal for solo enjoyment

Hand crank coffee grinders are low noise and don’t make as much noise as electric grinders that spin at high speeds to grind coffee beans. No matter what kind of electric grinder you use, the loud sound of it running can wake up your sleeping roommates, especially if you have a sleeping baby or child in the house, so you don’t want to wake them up at your own peril.
Hand-operated grinders do not require electricity and can be used in a wider range of situations than electric grinders, for example when travelling or camping.