Form v function... 

For a *designer*..... the **Function** would be a **visual metaphor**. The **Form** (if gears would work) is unimportant.

For an engineer that's reversed - an engineer would be concerned if the gears would work (Function).. it doesn't matter how they look (Form).

Designers are concerned with how things *look*, how easy things read, how dynamic things appear. In most cases... It honestly does not matter if gears would *actually* be functional, they just need to look nice and maintain overall design continuity. 

I wouldn't chalk this up to "laziness"... at least not that I've seen.. ignorance, perhaps. Realistically it can be a lack of software knowledge regarding how to achieve accuracy.. or time constraints preventing the acquisition of the necessary software knowledge. In fact, you'll find often there's merely 1 gear/sprocket that has just been copied and resized. I think **all your examples** show this. 

Most designers/illustrators I know are *fully aware* when they have gears which would not actually function (Most, not all.).... *"they still convey moving / tools / working / thinking.... that's all I need. Go away!"* 

- If I draw a table, I don't worry about showing dovetail joints.. or screws.. or nails.... or glue...
- If I draw a bell, I don't worry that the clanger is sized correctly based on the bell circumference....
- If I draw a rocket ship, I don't worry that the structure is aerodynamically correct or even feasible...
- If I draw a microphone... I don't worry that the wire mesh covering one end is the correct spacing and proportion as related to real world microphones...

... I just draw *what looks good and works for my needs*. It just has to *look* like what I intend. It's not a blue print or schematic.

I would *only* concern myself with functional gears if working on a piece that is destined to be seen by engineers, mechanics, etc... readers that would be fully aware of mechanical flaws in artwork. Just as if working on a medical piece, if I draw a stethoscope, scalpel, etc.,  I ensure they are accurate as they relate to the overall style of a piece.

Ultimately, functional gears or not greatly depends upon the *intended audience*. I used a gear image today in fact.. but it was for a financial piece ... a piece where no one is expecting some mechanical apparatus to be part of the pitch. It's inherently understood to be a metaphor. Therefore gear accuracy was unimportant. 

Although the image I used had no connotation of anything turning and connecting - which is most often what I'll do.. If I know gears/sprockets aren't actually functional, I configure them so it's abundantly clear they are non-functional and not just an idiot oversight were functionality is concerned. - I don't use images like your examples, head-on flat views. I intentionally always turn artwork like this to a 3/4 view or some other, more interesting, angle where "connectivity" is either hidden or clearly not viable.

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Also.. ya gotta factor in the the non-artist,  *"I just need a feakin' icon, man"* users. It's not *only* "designers" creating icons... I've seen some *horrifically inaccurate* objects in "logos" lately all because AI Image Generation has grown more popular. Just yesterday.. a Bike shop logo with a Bicycle that was completely non-functional, not only due to the sprocket but the handlebars and pedals as well!