After about 500 rounds, it doesn't appear to get any worse.
Don't push it and wait too long, unless you have a stainless pistol. After 3 or 4k with just lube, one of mine needed blasted to get cleaned.
I'll normally pull the slide off and do a quick wipe down somewhere between 750 and 1000 rounds, more often on my EDC (due to ammo prices, I don't shoot as much, and it tends to collect lint). They get wiped down once a week, or after they're shot. I also add a few pulls with a boresnake when they see rangetime.
At 2k they get detail stripped, thoroughly cleaned (brake cleaner required), parts inspected, and a new recoil spring installed. FP spring too, since its included.
A recoil spring will last a lot longer than 2k rounds, I just go ahead and change it when I clean it. Its easier to keep up with than every third time I clean it.
I'm not much for cleaning guns. Several folks have told me that something bad will happen if I dont, but it has yet too. I've got a kimber with well over 10K through it that I've cleaned five, mabye six times and its still as tight as it was the day I got it. The lockwork is is the only thing that's really shown any wear, and I cant really see it, but I know its worn, it has a 2.5 lb trigger.
ETA: I should note that I only shoot jacketed ammo....