Commissioning just one illustration made is not very effective.
Working on a system of illustrations makes more sense if you know how illustration software works.

But, of course, the question from a communications department always starts like this: ‘we want to explain how this service works’ or ‘show what this solution looks like.’

1: Think of the reader.

Silly me saying that all the time. But in “normal” companies, the inventors, the engineers, are in charge. These are eager to show what they can do, and how clever that solution is. The reader wants to know “what does that do for me, that product of yours? Would you listen to the buyer, you end up with use cases. Recognizable situations. You can show those.

2: Think about how and where that reader views your image.

You create a hefty visual for the website. But for insta, or twitter, or a trade show, it may not be appropriate. For those channels, you soon come up with a specific section, preferably for one target audience at a time. The illustration assignment then becomes “create an illustration system that allows us to serve all channels”.
For motion graphics or animations, you need illustrations made up of separate components.

3: Think about what you would like to make later on

What you will need furhter on in the process, you don’t know yet. Still: wouldn’t it be helpful to have illustrations in a style and type that you can easily add to later? Then make sure you:
do not work in a specific resolution (create vector illustrations or 3D illustrations that you can later re-render)
do not work in a restrictive color palette (RGB, never CMYK)
don’t get stuck with a peculiar perspective (do everything either “flat,” or isometric, or pure 3D)
Details that are temporary (or fashionable) you want to be able to easily remove or change; work modularly.

The stage

I always illustrate systematically. You start building a little world, so to speak, as early as the first drawing. With each subsequent assignment, this little world continues to fill up with backgrounds, users, scenery, specific applications and newer versions of the products. Just until you can answer each new illustration request very quickly because you have the components on the shelf.

Oh, there’s another point 4:

4: Make sure the illustration method is transferable

Once the style is developed, you don’t want to be stuck with a designer or illustrator. Ideally, you want to be able to create your own expressions with the individual components, even if it’s only a text layer that you can change. It’s even better if style, size and color palette are fixed so that an in-house illustrator, or a cheaper illustrator externally, can toe the line.