Greasing your razor is not mandatory to work properly if you regularly clean it.
But you can prevent that the inside mechanism stucks due to accumulation of limescale or shaving dirt, that are impossible to remove from
inside with the cleaning methods mentioned above.
Organic olive or sunflower oil leaves solid waste with aging, becomes hard and produces jam in the mechanism.
There are some other greases (motor, bicycle, electronics) that can have solid consistency, and are not recommended for this little mechanism
of the safety razors, because over the years they can turn a little tough and block the mechanism partially.
To grease your razor you should use mineral oil (non-organic).
NEVER USE ORGANIC OIL