The reason is prosaic - the laptop is a portable device, so it is quite fragile and it can be easily damaged by an accident.
Child or dog can drop it from the desktop or the couch - if you're unlucky, the screen may break.Does this mean that you have to buy a new computer? Absolutely not! You should take your broken laptop to the trusted computer service, or you can check if the warranty does cover this type of failure.
A laptop, often called a notebook, is a portable personal computer with a clamshell form factor, suitable for mobile use.Although originally there was a distinction between laptops and notebooks, the former being bigger and heavier than the latter, in modern usage there is often no longer any difference. Laptops are commonly used in a variety of settings, such as at work, in education, and for personal multimedia. A laptop combines the components and inputs of a desktop computer, including the display, speakers, a keyboard, and pointing devices (such as a touchpad or trackpad) into a single unit. Most modern-day laptops also have integrated webcams and built-in microphones.
The device can be powered either from a rechargeable battery or by mains electricity from an AC adapter.
Of course, a lot depends on how badly your PC is damaged.However you should noted, that repair is still cheaper than buying a new one.