As a WoW newbie, what took you way too long to find out?

I always assumed you could not turn while casting. I started at the end of pandaria and while leveling this never was an issue. I also mainly played a healer and heals always land anyway regardless of facing. Anyway everything is going fine, WoD launches and im enjoying the game while slowly start getting into more serious guilds.So come Blackrock Foundry I find myself healing my first Mythic boss. Beastlord Darmac. As a healer this fight has quite a bit of downtime, it is also a long fight so for the first part I would mainly spam Wrath to do a little bit of damage.However this boss also jumps around the room all the time to put a bleed on some ranged players. I remember carefully positioning my character so I could cast the Wrath and the boss would still probably be in front of me if he jumped to a player. But occasionally he still went for a player of the other side of me and my cast would finish and fizzle because the boss was behind me...I made a comment about it in vent and people did not really understand. Why didnt I just turn to the boss? I thought 'Well because I didnt want to break my cast duh..' but kept quiet because in my mind the doubt was there. Next pull I just tried it and it actually worked! My mind was actually blown. Never did I realize in all those months that you can just turn around while casting.It feel so silly thinking about it now but its one of those things that I just took for given while the game never forces you to it. I just didnt know better. Whats your prime example of newbie ignorance?tl;dr: Never knew (for many months) you could turn while casting. Only after complaining about having to cancel casts I saw the light.