For me, it’s however long a blade lasts.
My supply of blades are intentionally on my work bench, not by my saw. That way, when it’s time to change the blade,I take the blade out of the blade holder, stand up, put used blade in plastic pop/soda bottle on one workbench, take 3 steps over to other workbench, grab new blade, take 2 more steps, sit down at saw and put it in blade holder and away I go.
However, there are many a time that I’ll play with the Slinky that is on my bench, or look out the window and admire the view, or do whatever! I’m in no hurry when it comes to shop time. And yes, I do sell the vast majority of my work.
For what it’s worth, on 1/19, I hooked up a digital clock to my saw. Actual running time of the saw is 17.4 hours. In that time I have made 3 intarsia pieces, 12 birdhouse ornaments, and 3 penny drop games. To me, it’s eye opening how little my saw is actually running!