I mean, it depends on what you're cutting and what the purpose is. Are you cutting up a raw chuck roast to make stew? Or breaking down a subprimal cut into individual portions? Or are you carving a cooked rib roast for presentation on the plate? Or slicing a ham? How thick is what you're cutting? Etc...
If you're trying to produce the smoothest surface on a cooked piece of meat, it is best to use a large knife and pull in a single stroke. Sawing back and forth will produce visible lines on the meat which can make it look "mangled." Sometimes that matters. Sometimes it doesn't. Using a back-and-forth method can also make it difficult to produce cuts of uniform thickness (depending on what you're cutting) since you're making a bunch of strokes rapidly. That's not always the case, but it can be. When I'm carving something cooked, or breaking down a large cut into steaks/chops/whatever, I try to slice in as few motions as possible. Depending on thickness, this can be either a single stroke pulling only backwards (with a very long knife) or a "push forward, pull back" 1-2 slice on thicker items.
This isn't my video, but it nicely shows the "1-2" slice that I use on bigger items. Forgive the drum and bass soundtrack; it was the first video I found that showed the technique:
