Sim not responding immediately task/action

I've been having this issue a lot with and without mods, and my sims stand around or sit a lot as well doing absolutely nothing. Currently playing in my no mods/no cc save, which has never had any mods or cc used in it but this is still an issue. The issue worsens in larger households I find, but is still present in single households too. 

This happens to me too! And sometimes the game auto-cancels some actions. Like for instance playing on the computer - can't do it without pressing the chair and choose the option "sit" and THEN pressing the computer. Really weird