DRM turns music, movie and book purchases into rentals. You need permission from the seller in order to listen to or view what you bought.
If the seller shuts down the service, then you can lose access altogether.
Major League Baseball and Google have both killed access to purchased video in the past. Both relented after news coverage, but you shouldn't have to work with a reporter to get access to something you bought. In both cases the issue might well have been DRM and not the company, but the customers were still out of luck without intervention by the media.
Philips, Keurig and the printer industry anti-competitively use DRM to prevent other companies from creating competitive products.
Heck, John Deere uses DRM to prevent repairing your very expensive tractors. We need the Right to Repair what we've bought.
May 3rd, 2016 is this year's International Day Against DRM. Celebrate by purchasing some DRM-free content from producers that actually want you to have access to the content you've paid for.
#DayAgainstDRM