We typically wet clean/vac one time. CF brush before and after each play. Clean stylus properly after each side (very important, especially with modern styli).
Before we started using the new AIVS solutions I used to be able to dredge up a line of fluff after each play, presumably stuff not removed by the cleaning but loosened by the stylus. As often as not we'd have to reclean.
Since switching to AIVS fluids last summer that annoying problem has (nearly) disappeared. On 90% of LP's a post-play CF brushing dredges up - nothing. No line of dust to swipe off the record.
Aside from the sonic improvements, this also seems like evidence that a good wet cleaning/vacuuming with effective fluids need only be done once.
A small percentage of old, oft-played records does respond to repeat cleanings. It's likely that many passing styli over the years (not mine) ground up stuff and deposited against the vinyl walls, making it very difficult to remove. We don't buy obviously soiled records so we don't get this very often, but it does happen from time to time.