Positive or negative?
My brother (3.5) wears glasses, or is supposed to wear glasses. He’s not so good about it. He’s going through a “break it” stage, so his glasses certainly got the brunt of it. But he won’t wear it unless he’s bribed to (at home, because in school they make him keep it on).
But then it will also depend on the kid. My mother once asked someone how her kid kept her glasses on when she was little, and she said apparently, she had a high enough prescription that after a while (I think she got them before she was one) she realized that she can actually see better with them, so she started wearing them.
My older brother on the other hand – his prescription was rising too quickly, so the eye doctor gave him lenses. (Back then before disposables.) He wore them for a while, then lost them at the mikva one erev shabbos. He’s been back to glasses ever since (like 10 years).