I don't tend to quote books. Most of the time what I quote, refer to or repeat (always with proper credit given to whoever said it) is stuff like remarks I've run into in conversation (in offline life or online), in discussions I've seen/heard in one place or another, etc. I may occasionally refer to something I've read in non-fiction (often text) books; but that's not really a quote, instead it's more a matter of saying something like, "I read x book when ______, and it was pointed out that _______". I'm not above quoting myself sometimes (lol), and I'm not above creating my own sayings.
As far as quoting what other authors have said (in terms of "quotes as we think of quotes"), I don't make a habit of it and can't recall ever doing it. I may have. I've read a lot.
My "thing" is I don't really want to make my points by using the words of other people. It's not my instinct. Something else is that there's not much out there in books that I see worth quoting "as a quote". With non-fiction stuff, it's either worth taking in and assimilating; or else not worth remembering. I don't read fiction these days, so there's that. With classic works, it's been awhile for me; and I wasn't all that tuned into things like what was quotable when I was reading them. I got the main idea of those but can't say I saw anything worth quoting at the time when I read them. I'm not about to start looking for things to quote now because I'm not particularly a big fan of people's quoting great literature for the sake of quoting great literature.
On the other hand, I do seem to notice myself occasionally quoting things one or the other of my parents said that I've since seen, for myself, were absolutely correct. When I do that I'm not doing it to express myself, though. I'm doing to it either because I'm enjoying having seen something one of them said reveal itself to be true; or else because I'm trying to point out to someone how wise parents can be (lol). So it's a different kind of quoting with a different purpose.
Those parents I mentioned were big for encouraging their kids to think for themselves. Guess that's one reason I've never been one to express myself by using someone else's words. :)