A computer system comprises hardware and software. Hardware is the physical medium, for example: circuit boards, processors, keyboards etc. Software are computer programs like the Windows operating system, Internet Explorer, SyncBackFree etc.
Hardware doesn't last forever and breaks for many reasons. From components that fail like a keyboard with a key that doesn't work any more, to a hard drive that does not boot because of either mechanical wear and tear, or electronic problems.
A piece of hardware does not fail because our software is being used. You might equally think that Windows broke the hardware, or another of the many other software processes that were running at the time were responsible for your hardware problems. In truth, software was simply being used at the time the hardware failed. This is not surprising as hardware generally fails while actually being used when the physical demands on it are greatest.
Mechanical and electrical failures are common and occur just as easily on new hardware as with old. Components may be poorly produced, heat can cause the electronics to fail, and in the case of hard drives the physical deterioration of the magnetic medium is inevitable.
One of the principle reasons why a backup program like SyncBackFree/SE/Pro is crucial for anyone who doesn't want to risk losing their data, is to protect them against hardware damage and failure.