The desire to shape that amazing virtual world around me was quite strong from early on and eventually caused me to dabble into building a variety of things. Showing them off to friends in public, I started getting inquiries on where to get those items, which eventually led to the the establishment of the A.I. Toys brand and store.
I will admit to being a lazy builder. It's not about earning money, it's about the joy of building and the sense of accomplishment associated with it. Seeing people enjoy what you created is an additional reward, and a strong one at that.
While building is a fun pastime, finishing something up for sale is more of a chore. Marketing pictures need to be taken, vendor artwork created, advertising blurbs written and companion/manual notecards put together. The only thing that will convince me to put in that extra effort usually is someone "threatening" to buy something I have built. So if you see something I've built that's not for sale yet, just ask.