Some electric motors don't require as they are sealed and have a cotton like pad around the bearings where oil is kept soaked in it so that the electric motor is constantly lubricated.
Eventually after years the oil could start to go away and lose it's lubricating properties and cause electric motor to seize.
If your electric motor has no oil ports then it doesn't require oil but if the electric motor does have oil ports you should always oil the motor once a month or every few months or so depending on how often you use the electric motor.
As for electric car and electric vehicle motors they don't require engine oil like a gasoline or diesel engine needs oil as they don't have the complex moving parts like internal combustion engines do such as crankshafts, engine bearings, rods etc that need the lubrication constantly.
However electric car motors do have oil in the bearings that are sealed but they don't need anymore oil or oil changes like an internal combustion engine needs.
Electric car and electric vehicle motors have sealed bearings which are designed for a long life.
The best oil for electric motors is 3 in 1 motor oil or SAE 20 motor oil.
3 in 1 motor oil or 3 in 1 oil in general is best for electric motors for lubrication.
3 in 1 motor oil is the best for electric motor bearing lubrication.
SAE 20 motor oil can also work in electric motors for lubrication.
WD-40 is OK for electric motors when cleaning and freeing up any stuck components although WD-40 shouldn't be used as a lubricant for the bearings as WD-40 is not an actual lubricant but is instead mainly a cleaner and penetrating solvent.
3 in 1 motor oil is different than the regular 3 in 1 oil.
Some larger electric motors may require grease or a thicker oil depending on the size of the electric motor although most household sized electric motors can use 3 in 1 motor oil or SAE 20 motor oil.
10W 20 motor oil or other light oils can also work for small electric motors.
And for electric motors that need grease, the grease consistency preferred for electric motors is normally NLGI 2 or 3, with a base oil viscosity of 100-150 cSt @ 40°C or 104 F.