It seems that you enjoy making new sims, creating a backstory, designing their homes, then playing them for a while before wanting to move on to something different.
If you look through your post history you'll see many threads similar to this one. With the same advice given above.
We've helped you choose names, careers, aspirations, marriage partners for your Sims.
Why not just accept that this is your playstyle and you're not doing anything wrong.
Why not just continue what you've been doing and maybe one of your families will eventually motivate you to continue their story into the next generation. And the next.
