Sims 1 and 2 - I didn't even know mods existed as I had limited access to the internet.
Sims 3 - Now I had my own computer and high speed internet, so when I got tired of all the glitches in the game I went looking for answers. Found out about mods and never looked back. I think my first was NRAAS Master Controller, but I down loaded a lot which probably didn't help my game at all.
Sims 4 - Since I knew I enjoyed mods from 3, I went looking for some fairly soon after I got the game. If I had to guess, I'd say I probably started off with MCCC to give me more control over my game, but I can tell you I didn't stop there.