That largely would depend upon how and what you are using it for.
The general NRA recommendations are that you should clean your pistol after every firing session.
My General Advice is:
If the Pistol is your main home defensive arm, it should always be well cleaned and lubed.
If you Target Shoot only every once in a while and long periods go between Range Sessions, clean your Pistol, ASAP, so that fouling and corrosion do not set in.
If you are just using it for Target Shooting with only a few rounds thru it, on a regular basis, Clean and Lube after a minimum of 100 rounds. (I've gone 150 to 300 rounds or more on my PT92 and others.)
I have a 24/7 pro 45 I am trying to get as many rounds down range as I can afford lol I am at 8000 rounds as of this past week, I shoot 500 rounds through it every range trip and clean it when I get home. If you dont shoot that many rounds I would still clean it after each shooting session,