Earlier quoted context omitted.
Obviously it is not. You can read my question as how long did it take you to get enough traction in your side project to became a full time job. And still the answer will vary depend on how much do you spend in your side project, the market, your goals, etc. I hope no one decides to go full time with their pet projects because of the time they have spent on them!
Perhaps the post has changed but this is the title I see: "Ask HN: How long did you work on a side project until it was your full time job?" Adjusting it would definitely helps clarify if that's not what you meant. Perhaps, "How successful was your side project before you went full time?", or "How much MRR / traction... ?"
What I wanted to know it is the time. Any metric I ask about a project is not going to be good. MRR -> it depends on your expenses and if it is a peak of a trend or something constant; active users -> depends if you are building the next facebook or a Saas business; etc... Any metric is deep linked with the project and doesn't say anything by itself without a good understanding of the project and the market. I just wanted to know the time because I was curious about it, but you cannot claim any conclusions based on a single metric and without a deep knowledge of the business.