Rihanna peaked (in terms of artistry) the moment she lost interest, which is why the LOUD era will always be her best, because she still cared (which shows in her performances) and put effort in the way the era panned out. The girl simply doesn't give a damn anymore, which was fine for her bad girl image but now it just comes across as uninspired, resulting in short snappy eras surviving on the lead single + hype alone.