container for bulk fermentation/proofing It happens to me quite often that I make small batches of bread/pizza/focaccia dough that need to spend several hours in the fridge or at room temperature in a container with a lid
I've seen that many use containers in which the dough covers already the bottom and, in case of proofing, the dough rises in the vertical direction.
This definitely facilitates drawing volume markings to keep track of the rise. Is there a specific reason why to avoid containers that are too wide? Assuming of course that the container volume is enough to avoid overflowing.
Surface area. If the container is too wide, larger surface of the dough gets into contact with air. Dough can dry out, yeast/sourdough culture can behave differently (during aerobic fermentation the cells multiply, during anaerobic fermentation the yeast cells produce alcohol instead of multiplying).