you can have up to 6 accounts under the same payment of $14.99 a month. With that, everyone gets their own profile/playlists, no ads, and you can download your music offline for when you aren't able to stream. Where as with Soundcloud I was paying $11.99 a month just so I could listen ad free and download my music for offline listening when I didn't have cell service or wifi. Since I don't make music myself I wasn't getting all of the benefits of having an upgraded Soundcloud account. Not being able to stream is very rare, and I can still access my Soundlcoud profile and playlists for free.
Spotify makes it simple pick an artist I like and shuffle all of their music. I can add songs to a queue, create custom playlists, easily view top charts, and more. The best thing is that Spotify has both a mobile and desktop app, both of which work extremely well and are laid out great. Soundcloud however only has a buggy mobile app, and a lot of its features were not very user friendly. Oh, and there is a weekly release radar so you don’t have to keep up with every single release from your favorite artists.
One last thing, Spotify just seems to be more adopted. For example you can connect your Spotify account to your PS4,
and many other devices/apps. However I never ran into one single thing that connected to your Soundcloud account.