in terms of the consumer devices, the answer is fairly simple, they have a heavy emphasis on business, unlike iOS and Android, BBOS doesn’t have a lot of entertainment to offer, not many apps available in the BlackBerry World store, and not as much focus on media. BlackBerry devices are known for being reliable and secure, not fun, which is why many business and political leaders use them, they may not be good for playing Angry Birds, but they can be depended on.
Truthfully, BlackBerry devices are good, and could be competitive, they now have android compatibility, the famous BlackBerry Hub that let’s you read and respond to email, text, social media, etc… all in one place, built in FM tuners (some androids have this too though, Samsung particularly), robust web browsing capability, the ability to separate work/personal stuff, and so much more. All while holding onto the reliability and security the became known for.
But all the good was put aside for the fun factor, there was a shift in the smartphone industry, from reliability and functionality to more fun, people didn’t just wanted to make phone calls and keep a calendar like they used to, they wanted a computer in their pocket, they wanted to play games, check facebook, watch netflix, etc… BlackBerry didn’t change to accommodate those ‘fun’ users in time to be a real competitor to Android and iPhones, so they got relegated to the business customers, and those who value security.