` const yup = require(‘yup’);

const userSchema = yup.object({
    firstname: yup.string().required(),
    lastname: yup.string().required(),
    email: yup.string().email().optional(),
    password: yup.string().min(4).max(10).required(),

});

userSchema.validate()


module.exports = userSchema;

errors: [ 'password is a required field' ],`

The error only stopped when I replaced “required” for “optional” in each of the properties. Why is that?