[quote="Ginger"]
We don't need to buy new one as long as the older one is working fine and its best to save money for other important things
[/quote]

The best approach is the middle in everything. It is not required to buy new one each year and as long as old gadget still operational with some slowness you could save money however you may buy new one if it doesn't serve anymore for your work. This is to conclude everything.