A cracked device screen starts out bad and gets worse. Not only does a cracked screen obstruct content, but it also exposes the phone and the user to further damage. While a phone's screen may remain intact after falling against a hard surface dozens of times, repeated impacts weaken the glass screen and eventually lead to breakage. If your screen's cracked, it may be better to repair or replace the device than to ride it out.
It Gets Worse
A cracked phone screen is a broken phone screen and it's not going to get any better over time. In the worst-case scenario, a cracked or shattered touch screen will be so damaged that the capacitive touch functionality will no longer respond to finger gestures. Cracks indicate that the screen is no longer structurally sound; a phone with a cracked screen is more likely to shatter when dropped than a phone without a cracked screen. After the screen shatters you won't be able to see what's on the screen, making the device fairly useless. Additionally, finger oils and debris will work their way into the cracks and can further damage the screen over time.
Component Protection Loss
The glass cover on a cellular phone's touch screen not only functions as a user-interface device, but it also protects the inner workings of the device. It's safe to clean a non-cracked screen with a water-dampened cloth. If your screen's cracked, it's no longer able to keep liquids from working its way inside the phone, which makes cleaning the screen with water a risky affair because water inside the phone can short-out or break the device. Additionally, many phones tout water-resistant functionally, letting you submerge the device safely for several minutes If your phone was water resistant, it's not anymore if it's cracked.
You may get injured!
Unless you've got some mean finger callouses going on, there's a chance you'll cut yourself when you run your finger across the screen cracks. If the screen is severely cracked, you could end up with small glass splinters digging in to your skin. Additionally, glass shards may fall off of the screen when it's in your pocket, purse or bag, creating a safety hazard.
Attention to the details
A cracked screen is a distracting screen. Instead of being able to look at a screen and read content, you may have to scroll or reorient the phone to move the content you're trying to read outside of the cracked area. Spending the extra time to view content on a phone with a cracked screen makes viewing the phone a more significant distraction when multitasking. For example, screen cracks may take your eyes off the road for a few more seconds when driving and using a GPS app, which is a major safety risk.