She received a lot of money from Samsung to do so (more money than she would have made on actual album sales) + she was probably scared of getting dragged by the media when they compared her sales to Adele's, Taylor's, or Beyoncé's
She saw that her last 3 singles underperformed/flopped s she knew Anti would have flopped too. Its just an excuse to not be dragged( its not like she is not being)
Because she is aware of how this era has went. She knew the Navy suffered a lot waiting for this record, it was the least she could do. Also considering the tour is next month, it's pretty much the quickest way to get her music out to EVERYONE.