Because they have careless employees
Being from AZ, I notice this happens a lot here in WA. And it's a lot of drive throughs. So much that when I use one now, which is very rare, I check the order when it's given to me. This shocks the person at the window, one asked if something was wrong Sir, I simply reply No, I just want to make sure it's all correct before i get a few miles away from here. I think if more of us did this, it would cause those inside to pay more attention, assuming they're not doing it on purpose.
Ik I went and the service was so bad
Depends what time of day it was also. It seems that closer to closing time they don't care about serving their customers cold fries and incorrectly prepared food.
I recommend that you ask them to repeat the order back to you, some of the staff here do not speak English as their primary language.
Recommendation double check that they added cheese, that seems to be a fault for many fast food chains.
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