(DSLRs not compacts) How do people start with Nikon instead of Canon?

That's just an example I mean this as how do people start with any company over another one. Nikon over Canon stuck out in my mind because it feels like Canon is a little more popular than Nikon but I still see people with Nikons so it makes me curious how/why do people go with Nikon or another company over another.

My dad started with Canon all the way back with the D60 I think so I got into it with him.