I very often like/share/upvote comments just to promote stupidity of the author. My followers are fully aware that I like something stupid for the lulz, not to promote it. If author of a stupid comment thinks they're being liked, that's even better for the lulz.

I don't use twitter, but on both reddit and here I'd estimate around ten percent of my voting is misclicking. Phones make it too easy to accidentally press a button.

Bookmarking for another platform or another time. Some twitter interfaces have a bookmark affordance and some do not (the web doesn't, at least in my cohort).

These alternative uses is why people say often in their bio that "likes" do not imply endorsement, but it's so common to say that that I didn't even mention it on my bio, though of course it's still the case.