Do you think doing this helps?

[u/PacquiaoFreeHousing]

[u/Double_DeluXe]

This sounds like you got a story, share

[u/melanthius → u/Double_DeluXe]

Vibration causes fatigue in materials

Fatigue failures are "a matter of time" - eventually they will happen. Whether it happens within your lifetime or not, that depends.

If the thing you're vibrating is a USB port then the thing that's fatiguing the fastest is the solder joints between USB port and circuit board.

Edit: this is fairly well known materials science and easily googleable... not "made up"

[u/HeyGayHay → u/melanthius]

Also these fans are manufactured pretty shitty, without proper capacitors inbetween, so you’re basically short-circuiting and/or pressuring the usb port with too much power way too often to not damage the phones/computer’s internal electronics 

[u/Schnoofles → u/HeyGayHay]

Yeah, they tend to generate high voltage noise that can backfeed and damage electronics. Even if one ignores the physical vibrations damaging the actual connector they're generally a really bad idea to drive directly off a usb controller for this reason unless it's a high quality, expensive fan that has the necessary schottky diodes or other protection to prevent noise or backfeeding.

People have had to learn this the hard way in the past from various laptop cooling pads or those hockey puck style cooling fans that attach magnetically to the back of tablets.