Each of these could be a post unto itself, but I'm keeping it short, just some of the biggest frustrations I have with how social justice advocates screw up.
1. Playing oppression olympics.
It is not a goddamn competition folks. All this does is give rise to a heirarchy that hurts our efforts. It also alienates the fuck out of people with multiple minorities when minority groups make them leave their other oppressions at the door or basically tell them that the group doesn't care about their other oppression(s) because X oppression is sooooooooo much more important/worse.
2. People who can endlessly talk about what they want in an ally without applying one scrap of it to themselves.
If you are willing to complain about how poor other people are at being allies, it really helps if you're an ally to others. I know way too many people who can go on for hours about what they expect in an ally, and hours more about how they don't have to be an ally in return.
Seriously, not asking much here, but when you expect people to champion your voice and support you, it helps if you listen to them in turn when it comes to not doing oppressive shit that affects them. I am really tired of people who are all like "Allies against X-ism need to do blah de blah" then follow it up with being racist/sexist/disabilist/homophobic/transphobic/otherwise bigoted as hell then being privileged wankstains when asked to cut it the fuck out.
3. People having a fit about the major assholes in X group and holding X group responsible for all of them, but then mysteriously failing to do so when it comes to their own group assholes.
If you expect X group to reject their Hugo (which they bloody well should do), you also should be prepared to tell your own Hugos to sod the hell off. Solidarity isn't overlooking the assholery of people just because they're "one of us", solidarity is sticking together against oppression, not sticking together IN oppression.
If a prominent speaker in your group is an asshole? Find a new fucking prominent speaker. You can do better than someone who shits all over other minorities and people from your group who have other oppressions.
4. It is not a zero sum game, equal rights are not a finite thing, don't act like they are.
There are more than enough rights to go around, if your only issue with the inequality in society is that you're not one of the privileged in the status quo, you're doing it wrong.
We can have it all, if X group gets rights, that doesn't mean Y group is automatically not going to get them.
5. Relatively privileged individuals acting like having a small amount privilege they don't have is the same as having them all.
There is no fucking privilege that turns someone into a straight, rich, able bodied, white, cis man. You either get born one or you get born someone with some level of oppression. Seriously if you have loads of privilege and one oppression, then no, X person with the one privilege you don't have and multiple oppressions is not more privileged than you, the privilege you don't have is truly not that spectacular.
6. Acting like somehow prejudice doesn't interact with oppressions.
Someone calling a straight, rich, able bodied, white, cis man a "cracker" is no big deal. It won't really hurt anything but his feelings, but he and his situation should not be your measure for how prejudice affects everyone else. Someone with multiple oppressions being subject to prejudice by someone with multiple privileges is going to take a much heavier hit from prejudice, because people with privilege can do more to inflict harm.
I'm so sick of seeing social justice warriors argue that prejudice magically isn't a problem if someone has at least one privilege, typically the privilege they don't have. It doesn't work like that, the more oppressed the person is, the more serious prejudice is. Just because it isn't formalised oppression doesn't mean it doesn't add to the burden folks carry along with oppression.
If you do any of these? You really need to rethink social justice and come back when you're not part of the problem.