I’ve had it with this guy! I can’t stand how incredibly useless this character is, and I just have to get it off my chest.
Mordecai 
Let’s start from the top… Tundra Express… I usually accept “Mighty Morphin’” before I go there, and my “pal” Mordecai keeps destroying the pods that I need to complete that mission. Most of the time, he can’t even scratch the paint off the enemies, but this is apparently something he’s able to do. So he does it! All the time! The rest of the time, he shoots enemies that are behind buildings or under cover. Fast moving buzzards that he obviously can’t hit is also one of his favourites. The only time he actually manages to kill something, is when he steals a kill for me while I’m in FFYL. Thanks, Mordy!
To try and make things up to you, he offers you the guns he once won in the Underdome. Except he lost them. He also lost Moxxi, by the way. Butterfingers, eh?
In WEP, he manages to lose his best friend Bloodwing, only to have her experimented on, and then killed. Wow! Who doesn’t need a friend like that? Instead of trying to rescue BW, he just hangs around his cave, and keeps shooting things that he’s not able to kill. It’s not until BW dies that he manages to pull himself together and actually be supportive. Maybe we should have killed that bird earlier on, eh?
Back in Sanctuary, Moxxi cuts him off from the bar, so he has to hire you to go and get more booze for him. While you’re doing this, he and Moxxi tells the story about how she dumped him. He must have been hitting the bottle pretty hard even back then. And by now, you don’t have that much confidence in Mordecai, so when he offers you a sniper rifle as a reward, you instead go directly to Moxxi to get a pistol instead. She also pays you for the booze!
Roland is obviously aware of Mordecai’s uselessness, since he comes up with some bullshirt story about how Mordecai “needs to watch over the city” instead of coming to Thousand Cuts. To make things worse, he doesn’t even trust him to stay there on his own, so he has to leave Lilith behind to keep an eye on him. Because of this, you have to struggle your way to the top of Control Core Angel on your own. Lilith then slips away from Mordecai while he’s passed out drunk, and when she teams up with you and Roland, this becomes one too many things for Roland to worry about, so he drops his attention for a second, and… BAM! He dies, and Lilith gets kidnapped!
Back in Sanctuary, Mordecai is awake. He is now in charge, since Brick doesn’t really care about anything except punching and blowing stuff up. Mordecai is now so useless that he can’t even tell the people who live in Sanctuary that Roland is dead. You have to do it! He can’t even avenge Rolands death. You have to do it!
Later on when you get back to Sanctuary, after wrecking the bandits in Sawtooth Cauldron and after going up against the biggest damn robot on Pandora, Mordecai gives you a white rarity relic as a reward. Thanks again, Mordy! Your generosity is overwhelming!
In Hero’s Pass, he’s still the most useless sniper the Pandora has ever seen, and on top of that he now proves that he’s totally unsuited to pilot a ship. First he bumps in to another ship while it’s unloading, and then he crashes his own into the river of lava, taking Brick down with him. What a guy!
Later on, when you have killed the Warrior, saved Lilith and freed Pandora, he comes sneaking back with Brick, who obviously got banged up pretty bad, and tries to act like he was actually helpful during the whole campaign. Shame on you, Mordecai! Shame on you!