I hope this might help. The EOS R5 will increment focus from beginning focus point to infinity with infinity possibly defined by a standard circle of confusion. I have used as many as 30 shots in a focus stack with my EOS R5 when the camera was close to the nearest object. It seems to me the reason to set the number of shots small is to save storage space or avoid getting distant objects in focus, otherwise the camera will stop at infinity.
It might matter what F Number you are using. I sometimes set the focus increment all the way down to 1 and more often 2 or 3. I set the F Number to 6.3 or to 7.1 or to 8.0 as a good compromise between depth of field and small aperture diffraction blur. A smaller F Number would be expected to result in more shots while a larger F Number would result in fewer shots.
For me the biggest challenge is to find a day with no wind so that nothing in the scene is moving. On such a day I might try to photograph wildflowers. The second challenge for me is to get the initial focus set to the nearest object.
For the image below, I used F/8, the camera made 11 shots and I did not use all of them, the focus distance reported by the camera in metadata ranged from 0.62 meters to 1.33 meters. I used Canon DPP software to stack the raw images.
https://cam.start.canon/en/C003/manual/html/UG-03_Shooting-1_0300.html is the camera manual section.
https://www.rsok.com/~jrm/2021May19_birds_and_cats/2021may17_cornus_DC_1172.html
