Is AUTHOR wrong in the post ? POST : I'll try and keep this short.  Quick context.  I play D&amp;D with a group of 6 guys.  We meet each week, and the group is about 2 years old at this point.  One of the players (Adam) invited a coworker (Sarah) to join us for a few games.

So in D&amp;D there is a lot of math.  Not difficult math, but a lot of it.  Basically in combat you roll dice, add or subtract based on your character's stats, and use the final result to determine if you hit an enemy, how much damage you do, or if you escape a spell or trap.  It really is mostly single digit addition with some double digit thrown in.  Nothing too tricky.  At least not for most people.

Sarah has been playing with us for a few months now, and on average it takes her about 10 times as long to take a turn as it does anyone else at the table.  I don't mind someone being a bit slower on the mental math aspects of the game, but this woman actually has turns that go over 7-8 minutes because it takes her a full minute to add 3 single digit numbers together.  At first we thought it was because she was learning the rules and might have been nervous playing for the first time, but she has all the formulas written down.  It just takes her that long to do the calculations.  According to Adam she is known for being slow at work as well.

Well at this point she is taking so long that we are losing a lot of our limited game time just sitting around waiting on her to finish her turn.  A rotation at the table is basically all of us taking 1-2 minute turns, the DM taking 3-4 minutes (since he is controlling all the baddies so it takes awhile) and then Sarah taking almost as long as all of us combined.  It sucks.  It isn't fun only getting maybe 90 minutes of game done in a 3-4 hour session.

We group text after the game and talk about maybe removing Sarah from the group.  Everyone seems on board with the idea except for Adam who doesn't want to things to be awkward at work should she be kicked from the group.  He also argues that she is having a lot of fun which is true.  Even when she is struggling to do her turns she does seem to genuinely have fun.  So we agree to give her another chance if Adam can take some time at work and see if he can get her to speed her turns up a bit.  Adam agrees and all seems well.

It turns out we're all idiots, and Adam spending some time during lunch over the course of a week cannot magically make Sarah better at mental math.  She's just as slow as before, but now she looks frustrated when she is counting.  Adam had mentioned that we needed the game to go faster, and so now the pressure was on her and it definitely showed.  Now Sarah was more annoyed and short with us during the session and was clearly not having fun anymore.  By the end of the session Sarah ends up snapping at me and another player and started to cry.  We decided to cut the session off there after she stormed outside and Adam ended up comforting her and taking her home.

This was last week and other than a text saying "Sarah won't be doing D&amp;D anymore" he has been pretty quiet for all of us.

So am I the asshole here?  We basically introduced someone to a game they really enjoyed, but because she couldn't do math fast enough we ended up making her break down in tears and leave angry at us instead of having fun.  I was the primary driving force initially to remove her from the game, and I was definitely the most frustrated by her.  Now that it has happened though I just feel really guilty.