Things that make me just close tabs straight away: 1) Autoplaying videos, especially ads. 2) Pop-ups / overlays. 3) Loading lots of extra elements causing text to jump around. Especially true if I'm just browsing around and click on something that looks interesting, the above will take that thing from "this might be worth 30 seconds" to "not worth it". Why kill that little dopamine boost someone just got from clickin…
If you're lucky it loads fast and the x to close is somewhere visible. You're rarely lucky though.