Post History

As already said, [instructions are about helping the reader do the steps in the right order](https://writing.codidact.com/a/278003/278005) *without missing any of them.*

This, of course, can take different forms in different contexts.

Recipes is one example. Another that I am personally familiar with is airplane checklists, which have the pilot take a series of steps, usually manipulating or verifying controls or instruments, in a specific, proper sequence which has been developed to get proper results for what one is trying to do. Pilots are trained right from early basic training to follow checklists precisely because doing so reduces the risk of an error or omission.

Typically, this takes the form of some variation of "challenge - response" or "control or instrument - state"; such as "navigation lights - on", "flight controls - free and correct", "vacuum suction - green range" or even "propeller area - clear". For an example of what one might look like, [here](http://www.inetefb.com/CheckLists/Cessna_172S_Checklist.pdf) is one for a typical trainer (a Cessna 172S), and [here](https://flyuk.aero/assets/downloads/resources/checklists/UKV-PRD-B737-CHECKLIST-V2.pdf) is a partial checklist for a Boeing 737-700/800.

As you can tell, this is hardly proper English prose. It is, however, clear, specific *and* focuses on a single item at a time. With one item done, the pilot moves on to the next item on the checklist.

One specific airplane I've flown as a pilot has a pre-flight checklist that lumps together several items into one.

The result? Unless I am paying very close attention, it's *very* easy to miss a step that's buried in the middle of what's basically a block of compactly written text -- which more or less obviates the entire *purpose* of having the checklist in the first place, because the reason why one has the checklist at all is to ensure that none of the steps are missed.

Now, airplane checklists are a bit of an extreme case in no small part because of the potential consequences if a step is missed (really, airliners have crashed because a *single* control has been in the wrong position), but they have got to where they are over almost a century in part precisely because the format ensures that if only they are executed from top to bottom without jumping around, nothing is missed.

**Therefore,** if you want to make certain that nothing is missed, I would say to clearly delineate each step. If you want the prose to read more fluidly, and are willing to accept the fact that the reader will need to parse each part out of the text and especially if they are in a stressful situation or if a step takes a long time to perform might miss something, then by all means you can put multiple items in the same paragraph.