Technically there will always be a minute power spike when you turn it on, which is why often things go 'bang' when switched on, when previously they had worked fine.
Also, hard disks are more likely to fail at startup. As an example, the vast majority of drive failures on servers are after extended power cuts (where the UPS has also drained) becuase this is the first time the drives have been powered down, often in years.
However we are talking having hardware for much longer than your average 'hardcore' PC user would have. Perhaps your granny would experience a PSU failing becuase of old age, but i would suggest that most people on here don't have a PSU older than 5 years.