It honestly depends on who owns the restaurants. The BKs in my town will cut corners by taking an old burger/grilled chicken patty out of a container and toss it into the microwave, which is apparent when I bite into it and notice that the meat is harder than usual and tastes stale.I used to like BK when I was younger, but they seemed to have just shit the bed lately. None of the locations in my area seem to give a fuck anymore. Can't even be arsed to melt the cheese on your burger, their fries always taste old, nugs or chicken sandwiches are lukewarm at best. It's fast food and I shouldn't have very high expectations, but man, these clowns make McDonald's look decent in comparison.
If I want a fast food burger, I just go to Carl's Jr anymore.
By contrast, when I went to one out of town recently, the food was much fresher and I could even see them use the broiler for once!