system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What happened to Blackberry and why did they go from a sensation to being a rare sight?
gpt
They failed to adapt. 

Blackberry was the *only* option for business users, really. 

Then the iPhone came out and suddenly everyone wanted a friggin iPhone. Now us IT people went "Dude, Blackberry has a lot of business and, more importantly, *security* features that are really, really important, so no, you can't have an iPhone" which was OK for a while... but then the middle-managers wanted iPhones, and then the managers, and then the VPs, and then the CEOs... so suddenly the iPhone was an option for business users, too, and Blackberry seemed -- rightfully -- old and clunky. 

Blackberry didn't take the threat seriously, and when they finally got up and did something it was too little, too late and too crappy (Blackberry Storm, anyone? Ugh). 

The real surprise is that they're still around at all.