It’s not you are a stingy person but three small glasses,of wine over the course of an evening is stingy,
the issue is, when people arrive, unless you’re going to bums rush them ti the table then you will sit and have a drink or two and chat first. If you give them a small glass you’d expect to top it up. They may choose wine for that drink, you can’t say no really . So that’s two small glasses before dinner.
then dinner itself , it’s not great to control how much they have, like it’s not great to portion up and control the food consumption. So if you’re going to keeo folks glasses topped up, and give them a choice Ie red, white, rose or sparkling, you need to cater for enough for most folks to pick any one choice.
you can just say sorry I’ve only got white, if so then 10 would probably do it.
however the point remains, three small glasses of anything over a course of an evening is quite stingy.