Example of your own Home Sever / NAS Build Log | FreeNas 10
Ok, what's the reason?
First of all , many of people are dreaming about comfortable and reliable media-server at home.
Second, many of people think , that good NAS is an expensive thing. And the only way to get reliable server is to buy it.
Ofc, you could spend your money on some ready decisions , like Synology. But, if you have some old components and periphery, some old parts and a bit time to think and work , you can build your own NAS.