Lots of people do, and having a natural tremor when dealing with tiny stuff isn't even particularly uncommon(it becomes really obvious for a lot of people when trying to use high magnification binoculars and shit like that). That said, as long as you aren't full Michael J Fox status, it actually is possible with practice and techniques to get over it quite a bit. This guy's youtube channel, he covers terrain and mini painting, the MS stands for Multiple Sclerosis(along with having decent video production value to show wtf he's doing since his day job is apparently professional video production).
He doesn't go over it in every single video obviously, but there are things like... if you really have some motor problems, don't pick something like Chaos Space Marines with their tiny trim everywhere. Learning how to actually sit at the table and prop your arms/elbows/wrists for maximum stability, simply accepting that some days are going to be better than others for painting, and so on. It does work, and it is possible to get better over time even if you've got the opposite of natural talent.