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The one on the right to which you refer looks, IMHO, to have been fractured during manufacture - hence the very coarse unfinished look to the percussion flaking. My bad monior makes it impossible to see well but the one on the left looks to have been snapped during manufacture as well. So you are right, they are likely discards. If material is scarce they might rework the bits into different tools like scrapers, but in the clovis period those big percussion flakes knocked off in the process of making the knife were great sharp tools as-is for butchering even if the knife didn't work out, so they already had lots of perfect scrapers and shavers and there probably wasn't much incentive to spend extra time reworking mistakes. A snapped knife blade was not a big loss when the attempt to make it naturally provided hundreds of spinoff tools.

In the item on the right there is the additional problem of shelf fractures - they stop the progress of the flaking and so, make it impossible to thin the blade to the point of being useful. Even if it hadn't snapped the thing was headed for the trash pile. Sometimes you can get around shelf fractures but most of the time they just keep on stacking up on you and your "blank" gets narrower but not thinner.

Those big scallops left by the percussion removal of flakes were very sharp too, even if they look roughly serrated [google the Wenatchee caches] compared to the pressure flaking of more recent times; large rough scallops were essential to cut through thick hides and tendons of big game. The edges on new knives would start out looking very wavey, even crude, but would become more and more "refined" as they were resharpened. What looks most "refined," even and gracefully curved to us would actually be near the end of their useful life.