The new performance.now() function is supposed to have better accuracy than Date.now(). All of the sites I have read seem to only use the new function for measuring execution times with the aim of finding and improving performance - because Date.now() seems hopelessly inadequate for this.
But, besides not yet being fully implemented in all browsers, is there any reason to ever use Date.now() again? Or seen another way, why on earth don't they just fix Date.now()?