There are three reasons why dogs turn food-shy: their food isn't fresh; their food is boring; their stomach is upset or they are feeling unwell or distressed.
Item No. 1: We all know that dogs have extreme powers of smell -- reputedly anywhere from 10,000 times to 100,000 times more acute than a human's. This might mean that although the food you're giving him seems fine to you, the dog has detected the presence of unacceptable bacteria. Are you storing kibble in an airtight container, and is it fairly cool or have you been delving into the same huge kibble bag in the same hot kitchen in the summer for a long time? Kibble is provided with tocopherol or Vitamin E, but that's a preservative to enhance the food's keep-time, not to make it imperishable. Also, those cold cuts you've had in the fridge for a month may not be safe for anyone at this point -- even your tolerant canine.
Item No. 2: Puppies when very young will tend to eat anything you give them. It's kibble for breakfast again! And since you are still feeding them lunch, it's the same kibble for lunch again! And oh look, kibble all over again for dinner! This pales after a while. I feed my dog kibble twice a day (she is now nearly 8 years old), but she never knows what I'm going to put on the top, since I vary the fresh-food component of her meals a great deal. If we have suitable left-overs from our own dinners, I give her that; if I'm frying eggs and turkey bacon, I'll give her some of that; or I'll open a tin of fish and give her the juice and some of the meat from that -- often mixed in with a dog-safe vegetable (her favourite is cauliflower). I also heat water to provide a sort of soup: I test it with my finger to make sure it's not too hot, but I don't give her tepid water, either. Hot water (or re-heated cauliflower boil-water, or chicken broth) intensifies the flavour of her food, just as it does for humans.
Item No. 3: For reasons emotional or physical, your dog at times may not be willing to eat. Or she may want to eat, but find the hard kibble too difficult to digest (just as you might only want a bowl of soup rather than a full-course meal with all the fixings when you don't feel well). At these times it is fine to give your dog a soft squishy meal that goes down easily and sits comfortably in the stomach. Rice is ideal for this, mixed with fresh succulent meat or tinned meat or fish, perhaps with peas and gratings of cheese. On this occasion, hold the kibble and the dry biscuits: having a few soft meals won't do the dog any harm, will provide comfort, and will also keep his or her blood sugar on an even keel.
By the way, there's no need to throw out a perfectly good meal if your dog won't eat it right now. I drain the liquid from the refused bowl and put it aside for later, keeping the kibble somewhat dry, and then refrigerate them both. As long as the meal has retained a degree of crispness (and isn't soggy), I can usually feed it to my dog, with fresh toppings, once she has recovered her appetite.