It was rushed to completed status.
FYI. The story was NOT rushed to completion.
Callisto was two years in the making and had a well thought out adventure plot that gave a realistic harem experience for the majority of the game with a choice of several realistic outcomes in the end. The fact that, with the Sci-Fi environment (world) scenario it created, it stands out as the most realistic adult adventure Sci-Fi story I've yet seen on the web. The theme may have been sci-fi fantasy but the individual personalities and relationships were well thought out, had deep backstory development and were very true to life.
Now I will say that there might be one additional logical ending scenario one could imagine, but even that wouldn't probably satisfy those who want a 'harem ending fantasy'. Sorry for you guys with the harem ending fetish but this is a more realistic series of endings, possibly the best you could expect in real life. If you like living in a harem, go back and play it again.
But don't say it was rushed because I'm here to tell you it wasn't.