How many times do you typically use a DE blade ?

I average between 3-5 shaves before I replace the blade. Max I have push a blade is about 7 shaves, after the 5th shave with Merkur Super or Crystals, my bread notices a little tug, still cuts, but that's when I know its time for a replacement.

Once and away

I'm experimenting, inspired by a post on another site. The gist was that our dads and grandfathers often shaved with a blade for a month before changing it. Blades might have been made to last longer compared with modern blades but they're wafers of sharpened steel, how much can they change? Well maybe plenty. But so far I'm at the end of my second week with a Gillette Wilkinson Sword made in India and it's still good. I shave daily and have a coarse beard. When it starts to tug or feels rough I'll change it.

Mostly 1-2 times, except for AC blades, those I will typically use 5-7 times

Typically 4-5, may take it up to 7 if the blade performs especially well and still feels sharp.

Blades can last a long time, but there's a zone of diminished returns where it doesn't shave as effectively even before it starts tugging.

The first 4-5 shaves are usually the best, no reason to experience that shaving experience degradation in order to save a fraction of a penny.

Blades are cheap.