I knew a guy like this. He also had 2-3 other bikes that he actually rode, but he spend a lot of time and effort (and money) building his Dream Bike. He was always waiting for some part to be shipped from some tiny manufacturer in Italy or Spain or Japan or Canada, and by the time it arrived he would have read about this other company that had an even smaller/thinner/lighter part, so he would order that as well and wait until he had both parts before meticulously compare them. And once he had managed to finally assemble a complete bike it wouldn't take many rides before either something broke or he decided something wasn't quite perfect so he would take the bike apart again and try to find an even more perfect part.

i built my own bike when i was young, but mainly because it was cheaper to get a quality bike that way and easier than saving up the money for a brand new bike. in the end riding is more interesting, so now that i can afford it, i just buy what i need.