3. Public relations agencies and candidates who who add you to email lists without first asking your permission so you have to go searching for an unsubscribe button. Most of the time I could care less about their issues and frequently, it should be obvious to them I oppose their position.
4. Email providers that don't let you mass delete emails with one click. Most require two clicks (like a checkmark next to each one you want to delete and then you have to click to delete them. AOL had a trash bucket at the end of each email header so you can click the can and it's gone, no extra steps. You can just look at your list of 300 new mails and click the delete button instead of the open button. Much better. (But AOL has other bad habits now, like too many ads and autoplay video of some irrelevant reporter on every news article. Memo to AOL: We do know how to read, we don't need you to read aloud to us. It adds nothing and in fact makes me close your window as fast as I can to avoid it and read the news at another site.
5. Not providing dates of news articles (causing readers to waste time searching the news site to figure out if the news is current or old. Frequently, these are old articles hidden under a tag like "related news articles." But some sites just don't bother with dates at all.
I could probably get to ten if I tried, but five is enough for now. Do you have any to add?
Update: Number 6: The overuse of social media sharing buttons and "other articles you might be interested in" that overlap onto the screen space of the article I'm reading.