What is the purpose of setting an object's priority?

Question

In Oxygen Not Included, the player can set priorities (1 being lowest, 9 being highest) for a number of things. For tasks like digging or building, this makes perfect sense to me.

What does it mean to set the priority of an object or station, such as a power generator, a cooking station, or an Outhouse/Latrine?

(Because this game is in the early release stage, I understand/expect/acknowledge that this Q&A may become irrelevant in future releases. Still, this does not appear to be discussed, so it may be useful to others. I am using Development Build OC-256131 in mid-March 2018.)

Answer 1

From the wiki article on priority (https://oxygennotincluded.gamepedia.com/Priority):

Priority can be set on actions and buildings in your colony. Your Duplicants will complete actions and tend to buildings starting with the highest priority (9) first and the lowest priority (1) last.

If multiple items are set to the same priority, Duplicants will complete mopping first, then construction of buildings, followed by construction of wires, pipes, and tiles, then tending to existing buildings (delivering refills) and sweeping, then lastly, digging. Keep in mind, no matter what priorities you have set, Duplicants will always take care of their personal needs (bathroom, eating, sleeping) when the need arises. The only way to bypass this is by toggling on Red Alert, putting the colony in a state of emergency, and forcing the Duplicants to ignore their basic needs.

so the priority on buildings is so that you can let your Duplicants deliver refills to a specific building before other buildings.

Answer 2

A typical early game scenario might be that you have a large supply of dirt and water, and need to cook Mush Fry for food.

This involves two different cooking stations: the Microbe Musher to make Mush Bar, and the Grill to fry Mush Bar into Mush Fry.

Let's say you have 1 person assigned to cooking and forbid people from eating Mush bars, allowing them only to eat the end product, Mush Fry. This increases the number of calories they get, improves morale compared to eating Mush Bars, and is safer since frying removes bacteria.

If your priorities on the Microbe Musher and Grill are set wrong, so that the Musher has higher priority, then the cook will make Mush bars forever, never start frying them, and everyone will starve since you have a large stockpile of forbidden Mush Bars.

If the priorities are set so the grill has higher priority, the cook will make 1 Mush bar, then fry it, then get back to make 1 new mush bar, fry that one, and so on, alternating between the two stations and always frying a mush bar if one is available.

Another example would be where you want to prioritise between two recipes in the same station. Since this is not possible, you could build for example two Microbe Mushers, set one to high priority to make Liceloaf, and the other to lower priority to make Mush bars. As long as Meal Lice is available, Liceloaf will be made, but when you run out of it, you have a fallback of mush bar production which is worse food but still keeps people alive.