Adobe Illustrator brush tool is great in that when you draw something, it smoothes your lines.
That’s great if you want that. But sometimes we want illustrator to respect the jaggedness of your drawing, and not smooth things out so much (like if you are drawing a box by hand).
To reduce the smoothness, double click the brush and drop the fidelity down to 0 (or as low as you can go).
This will remove the smoothness, and make your lines less smooth, and more jagged.
The Agile Warrior 
Jun 23, 2016 @ 10:16:36
Hey there, I’ve created a nice tool for mac that works system-wide and smoothes out any freehand movement. Have a look at hejstylus.com. Cheers, E
Aug 20, 2018 @ 19:59:09
I am losing my mind, cuz after newest update, now there is only one slider in paintbrush tool option, that does not affect the smoothing of the brush. Is there some other way to change it?
Apr 13, 2019 @ 05:09:50
while you on your brush tool press the enter key
May 23, 2022 @ 15:55:13
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