Version numbers have almost nothing to do with the actual progress of development and there's no standardization from developer to developer. People assume all the time that any version number above 1 must be a completed game, but that might not be the case at all. They also often assume the number after the period is a decimal, and that a 0.9 version number is 90% done, in reality it's just the 9th release and the next release could be .10, then .11, and so on.