The vast majority of ingredients are sourced from a central kitchen. Sauces, packaging, all meat products, rolls are from head office, without exception.
Fruit and veg can be independently sourced but the product must adhere to specific standards.
Coldrinks from ABI.
There a number of variables at play that affect the quality of the end product. Our patties are not cooked on order. They precooked and held in a bainmarie. The longer they sit in the bainmarie the further the quality deteriorates. It's not massive degradation and for most it would be barely noticeable... unless that patty has sat there for 2 hours or longer. That'll you'll notice.
If correct grilling procedures are not followed, this too will affect the end product! Stock arrives frozen and needs to be correctly defrosted before cooking. 48 hours in the coldroom for example...
In fact, if we look at all the elements that make up a burger, it's pretty easy to stuff it up. Rule of thump though, avoid quiet stores, avoid them after they've just opened (good chance you'll get a patty precooked the night before, even though it's mandatory to destroy left overs at the end of the day), request a freshly grilled patty, tell them you prepared to wait...