I have been working on a game as a side project for 10 years now. Why such a long time? It started when I was freelancing and carried on through full-time jobs, a marriage and now a small child. I am lucky if I can get one hour a day to work on it - but as others mentioned here, the best time to work on it is before your main job, otherwise I am too tired to code after a full day of software development, childcare, and home chores. I really wish I can finish it some day and show it here.