Why is MoP so bugged?

I've been playing MoP for a bit now using the Warmane client, and I've encountered several quest bugs. The quest "Young and Vicious" doesn't work properly, and the quest "Ride On" doesn't give me the option to get a ride to Razorhill when I talk to Raider Jhash. The quest "Unexpected Results" is bugged too, as whenever I log off and then back on, the quest is always there even if I turned it in in my previous session. The quest called "Never Trust a Big Barb and a Smile" isn't working as well, as whenever I place down the quest item. it seems to do nothing. Is everyone encountering these bugs or is it just me?

Newer expansion, younger development cycle, and the focus is on older expansions right now. And most likely no, it is not just you experiencing them.
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