I had an experience recently where I ordered sandwiches for myself and for a friend but things didn't go very well. The order was placed over the phone for a carry-out order. I ordered a turkey-and-cheese and asked for it to be "plain." Then I ordered my sandwich without any special modifications.
When we arrived at our destination and opened up our order, my friend's order was wrong. Usually, the friend would pick undesired ingredients off, but this sandwich had mayonnaise which cannot be completely eliminated. The friend was angry, as the lunch was ruined.
A word to my picky friends: it is on you to get your order straight. While the anecdote is a true story, it is not unique to her nor to others I know who choose to order their food in a manner other than the way the restaurant menu dictates.
Here are a few tips to help the restaurant get your order correct every time. First, ask for the things you want in your food, not what you don't want. Second, have the order repeated back to you (that was my mistake.) Last, if you have someone else do your ordering for you, help them get the order right by asking them nicely to order the right way.
Finally, don't get bent out of shape when your order comes back wrong. People make mistakes. Nobody is out to get you. If you want it right every time, either cook for yourself, go to salad bars and buffets, or go to restaurants where your food of choice is supposed to be built-to-order.