Her writers don't really care about writing "good" lyrics. They know most people like simple songs. The more words, the more difficult it is to sing along.
Nowadays, lets give to Adele's the prize of 'songs with lyrics', fits perfect with her music style. On Rihanna's very start she sang songs with words but this industry forced her to change. Although she doesn't write her song, something that she could really care about, this latest album was a festival of songs with repeated verses, and she must to go on if that's what'll put some food on her plate. Let's just chill, dance to the beat and watch how it ends.